PrepPros' 2024 ACT Math Test Full Explanation By Perfect Scorer + Math Equations & Strategies

[@preppros]

Improve your ACT score by 3 points, GUARANTEED! My Ultimate ACT Course has 70+ hours of videos where I teach you everything you need to know to crush the ACT. Sign up for a Free Trial (no credit card needed): www.preppros.io/act-course. Want the best ACT Math Book ever written and a video course to go with it?? Get a copy of the PrepPros Complete Guide to ACT Math (link in video description) and sign up for my ACT Math Course, which has 30+ hours of videos and over 1,250 practice questions. The free trial has 2 full chapters of the book included: www.preppros.io/act-math-course.

[@lucianorodriguez9843]

Hey, I just wanted to say I took the ACT for the final time two weeks ago and I just got my scores yesterday, and after watching a lot of your videos, I managed to get a 31 which will help pay for about a quarter of my college. Thank you sooo much!

[@preppros]

That’s great to hear! Congrats!

[@nassa8334]

yeah i’m cooked

[@AnnieLeigh111]

Me too. The first 15 which were suppose to be easy I struggled with 💀

[@shancharles459]

Same bruh , I decided to binge watch this the day BEFORE I take the damn test😭😭😭😭😭

[@kim_jieun06]

Nah frr bro and my exam is like in 2 hours and 22 minutes

[@tupapaaaaa]

@@shancharles459im here an hour and a half before 💀🙏🏻

[@shancharles459]

@@tupapaaaaa I hope it went well with you dear 🙏😭😭😭

[@hqs9585]

Problem 25. You could use (14^2 - 13^2) as (14-13)(14+13)= 1*27 and so on no need to multiply. NICE TRICK!

[@Kai._Star]

Taking the ACT July 13th (in 15 days as of writing)! I'm aiming for a composite of 30-36 hopefully 34 or higher. Math is my worst subject right now but this video and the free course are definitely helping a ton! Wish me luck and a good luck to everyone else taking it!

[@the.cynical.0ne]

Im taking it on the 13th too!!! praying for a better math score and hoping for a high 30's composite aswell :) best of luck to you!!

[@Goals9]

Same here I am praying to get atleast a 25+ Act math section

[@Ittoara55]

Same here! I’ll pray for yalls success! 😤 You got this, don’t be nervous!

[@Goals9]

@@Ittoara55 thank you I try to stay calm

[@Ittoara55]

@@Goals9 cuz, if I do well on this then I don’t kinda have to worry bout my SAT. Cuz I got a 780 😭 and I REALLY need to improve that

[@Literallymefr912]

Thank you for providing for us students that may not be able to afford study materials! This was very helpful, and if it was economically a good choice for me at the time I would have bought your course. This explanation has helped me a lot, thank you for making it detailed enough to not be confusing!

[@Flufflebean]

Taking it tomorrow morning, I've studied using your videos and others for around 5 hours every day for a week and I still don't feel prepared lol. My average score for the practice tests in a 30. We'll see i guess. Hoping for a perfect score, or at least close.

[@yaboiheadnappy]

Whatchu make?

[@Thats_Alexander]

What did you get have you got you’re scores back?

[@Bluphoriia]

what did you get…i’m in your position rn please say something

[@Thats_Alexander]

@@Bluphoriia I passed it

[@Goals9]

@@Thats_Alexander what was your score?

[@CaptainDoge1]

For question 9, with more complicated matrix problems some students may find it easier to solve with a graphing calculator. If you have a calculator like the TI-84 you can hit 2nd > x^-1 (matrix) and go to edit. Here if you hit enter on a letter, for this let's just say [A], you can put in the dimensions of the matrix box (in this question's case 2x2) and then put in the numbers in. You can then put in the numbers of the second matrix box into a second letter ([B] for example) . Then you can 2nd > Mode (Quit) and go back intro Matrix and this time select your matrix boxes from NAMES. Now you can just put, [A] + 3[B] and you would get your answer. Once you get used to the process, it goes by super quick.

[@hqs9585]

problem 18: Y is the sum of score of the 6 students. X is the score needed by Mateo. Then Y/6 =79, y =474. Now (y+x)/7 = 81 then substitution leads tp x = 93.

[@bazil4146]

I wish I knew this video sooner.

[@kim_jieun06]

My ACT math 1 is in 7 hours hopefully I can do well in it

[@wonderfuljackson8941]

What did u get?

[@dokducky2863]

@@wonderfuljackson8941 they will get score nexr two weekend.

[@rajkothari2639]

Great Video. I am aiming for a 35-36 on the Math Section this upcoming July 15 ACT. Your math playlist has helped me a lot. Do you have any last minute tips. I also suffer major testing anxiety so any tips for that as well will be appreciated. Thank you.

[@preppros]

Get a copy of my book and work through all the level 3 and 4 practice questions. The book has a 4 level system to make it easy to use for students of all levels. The level 3 and 4 questions are similar to the hard ones at the back of the ACT from questions 45-60, so they will give you lots of practice on those more challenging types of questions. If you are an international student and the book will take too long to arrive, you can email me at [e-mail] for a way to purchase a PDF copy. Also memorize all the important equations. I have a video here where I cover them: kzbin.info/www/bejne/rJWpc5hrl5eAaZY

[@Caseisgreat]

how much did u get

[@prajaygutti7992]

what did you get?

[@DanaMedhat]

Thankyou so much please do for the English test!!

[@siratmokha4526]

I think there is an error on the answer for 55. You calculation you only divided by 5280 and forgot to multiply 1.2 from 5280. I think the answer should be B

[@preppros]

Yes, you are absolutely right. The correct answer is B. That's why you should always check you work on the real test to help avoid silly mistakes like that one.

[@simulationgf]

i am so mad i spent 10 mins screaming at the screen crying bcz i thought i was wrong I'm gonna screan@@preppros

[@ferbsman]

thanks for pointing that out! I was worried I wasn't doing the math right

[@archirose3800]

@@preppros I was freaking out because I just couldn't see what I did wrong, do you mind pinning this comment so people know for sure?

[@AlexaHernandez-uj1xs]

Im taking mine this wednesday and I found out on friday so I had no time to really get prepared and study and my parents really really want me to pass and i'm so nervous but at the same time i feel like i'll be okay and i'll pass it. The only part i'm worried about is the math part because i've never really been good at math and the way we have to use the answers to solve the problem is the one that gets me most nervous because the people i see on youtube pull out numbers and create equations that i would never ever think about doing so that's the part. tomorrow can't study because i saw in a video to have a fresh mind and eat good and sleep a lot before the test. if i pass it ill reply to this video saying it but if i don't reply then 1. i passed it but i was so excited that i forgot or 2. i didn't pass it which hopefully not gonna happen. wish me luckkk!

[@atlas823]

please tell me you passed it cause am scared as hell i will fail mine

[@honeyspirit]

So you didn't pass it....? It's been 2 months and no reply...

[@Sethwasson555]

@@honeyspirityes I did pass !!

[@honeyspirit]

@@Sethwasson555 OH THANK GOD OKAY!!! Im taking my ACT on the 27th and I started panicking 😭😭

[@Generalstore83]

That so funny because my teacher told us on Friday that we were taking the test on Tuesday (tomorrow). I have been trying to study some strategies specifically for the math section since I also struggle. When I took it the first time I scored average so I’m hoping to get higher 🤞but if I don’t I’m fine just as long as I don’t go lower than my last test.

[@Literallymefr912]

Man, is question 30 really in the ACT? I'd consider it ambiguous because the wording could mean that 14 exclusively play soccer, 10 exclusively play basketball, and 4 students separate from those 24 are in both. This would mean that 28 students play a sport, leaving 2 that play neither. Like if they were all answers on a survey, there would be 28 separate sports players response, with a question like: "Do you 1) play soccer, 2) play basketball, 3) both, 4) neither? "

[@elisefarmer7392]

Question 17: I guess I’m not too familiar with absolute value questions, but could you explain why the -1/2 wasn’t turned positive?

[@preppros]

The -1/2 is not inside the absolute value bars.

[@jujucc8154]

I paused on #55 and racked my brain trying to figure out how to convert the volume into square feet just to unpause and realize that it was just the typo and my original answer was correct T_T overall I really liked studying this video because this is one of the few unofficial practice tests that has identical questions to some of the official ones from the red book and I recognized many types of questions that the explanations are nice. A lot of typos though like interest on #19 and second school instead of second class instead on #50 lol I didn't see those until I was reading back my notes. Also on #55 I did it a little differently but I got B instead of C and I don't know why because what I did is I converted 1.2s into (1/3000) of an hour and 200.4 ft into 0.0379545455 or (167/4400) of a mile and then with that I have Distance = (167/4400) and Time = (1/3000) so D/T = (2505/22) or 113.86 but now I am not sure if I am doing wrong. I am more familiar with this way rather than the scientific conversion way

[@preppros]

I'm glad to hear that you enjoyed the video and found the questions to accurately reflect the ACT. If you ever need more practice, grab a copy of my ACT Math Book (PrepPros Complete Guide to ACT Math), which has lots more practice questions that looks and feel just like official ACTs. For #55, your reasoning and answer are correct. The answer is B and not C. I made a mistake in the video and forgot to multiply by the 1.2.

[@lxtch5817]

1:05:37

[@hqs9585]

problem 36: typo h = 6 not minus 6

[@jojo.cowboys]

For question 46 would using the same side lengths affect your answer since the question is asking for the side lengths of a rectangle and not a square?

[@preppros]

No, it would not affect the answer, as the percentage changes affect the changes to the total area in the same way.

[@brielletila-cohen3744]

what type of calculator is best to use for the act?

[@preppros]

I always advise students to use a calculator they are comfortable with. If you know how to use graphing calculators like the TI-84, those are best, as they have added capabilities. Only downside is they are more expensive. If you are not comfortable with those, you can just get a regular scientific calculator. I like the TI-30 XS.

[@rosemary9661]

I was wondering for number 58, if you are allowed to have a square root in the denominator since it’s variables?

[@preppros]

The rule is the same with variables or numbers. In 58, the answer choice just had square roots in the bottom as well, so we did not have to rationalize it. Sometimes, the ACT answer choices have square roots in the denominators and other times you must rationalize the answer to remove the square roots.

[@irenewithwonder]

30) you said 10+4+6, but 4 is already included in 10 and 6?

[@preppros]

No, the 4 is for the students who play both sports. The 10 is for soccer only and the 6 is for baseball only. Rewatch my explanation again to make sure you are clear on the reasoning that I used to solve this so that you can get these correct on your own.

[@jaredsanchez6705]

Is the book similar to the real test on questions wise.

[@jaredsanchez6705]

??

[@preppros]

Yes, the questions are written to look just like real ACT questions.

[@DizzyandFrizzy]

Problem 32: Don't you round UP when presented with .5?

[@Talwyna]

Is there a typo on question 48? It seems you solved cubic feet to get answer "D" and the question requests "... in square feet"

[@preppros]

Good catch! Yes, questions 48 has a typo. It should be cubic feet not square feet since we are solving for a volume not an area.

[@rosegokublack9658]

when will you have the english, science, and reading tests on the free trial

[@preppros]

They are already included in the Ultimate ACT Course Free trial, which is separate from the math free trial in case you only signed up for that one so far.

[@rosegokublack9658]

@@preppros if i got a 28 on my first act, how hard would i have to study to get a 36 or do i just do pratice tests

[@preppros]

@@rosegokublack9658 You'll have to both study a lot and do a lot of practice tests to get to a 36. A more realistic goal from your starting point is probably a 33/34. Get to that score first then see if you can keep going up to a 35/36.

[@ShaunIsYawning]

On number 46, why do you multiply by .55 instead of .45?

[@preppros]

Since we are decreasing by 45%, we do 1-0.45 = 0.55. Decreasing by 45% means that the width is 55% of the original width.

[@dagimkiflu5615]

Thanks for all your help Prep Pros. I just wanted to ask if it was possible for me to get a reduced price for the Ultimate Act course as my act test is a month away and I don't have the money to pay for the Ultimate Act Course. It would be very helpful in my preparation since I am aiming for a pretty high score

[@preppros]

Send me an email at [e-mail]. For students/families who cannot afford the full price of the course, we do offer scholarships and discounts. With the Ultimate ACT Course, I really do want to provide amazing ACT Prep for anyone no matter your financial situation.

[@SarahBadawi-u7l]

Hello sir , is this for act math 1 or math 2 ?

[@preppros]

Neither. This is the math section of the full ACT exam. The act math 1 and math 2 exams are subject tests for international students.

[@SarahBadawi-u7l]

so, sir is it okay if I study for my act math 1 and math2 from your videos or the material is different for the act math section from the act math 1 and math 2?@@preppros

[@boboboaaa8050]

24. 30, 31, 32are difficult for me to understand 🙁

[@lxtch5817]

42:13

[@thedelaunesband1405]

Learn: 24:21

[@speedtrial1473]

Do you think the exam is easier than the practice ones? i am aiming for a 26+ and i am pretty good at maths do you think that's possible

[@preppros]

As long as you are using official practice ACT tests, the real test is going to be just as hard (or harder) than the practice ones. The ACT Math has gotten more difficult over the past few years, so do not expect the real test to feel easier.

[@speedtrial1473]

@@preppros is the one in the video like the real ACT tests in your opinion?

[@preppros]

@@speedtrial1473 yes

[@haveahollyjollychristmasxo2447]

Is this test really from 2023? like will most of these questions be similar to any of the upcoming 2023 act tests?

[@preppros]

While it is impossible to predict what will be on upcoming ACTs test dates, the questions on this practice ACT test are written to look just like real ACT questions. This test was written in 2023 and many of the topics/question types on this practice test are very likely to appear on future ACTs.

[@zetseatzinabu]

for question number 46 you take the same number for the base and the hight but its rectangle second mistake you said take any number but i try to solve it it wont work.

[@waadmohamed9618]

You had one for the 2022-2023 but I can’t find it where is it ?

[@preppros]

I had to take it down from KZbin due to copyright issues with the ACT.

[@loser_town8287]

17:06

[@lelemon946]

for question 42. why can it not be k? dividing exponents basically means subtracting right?

[@preppros]

The a term has to be on the bottom since it is a negative exponent. I'd recommend that you rewatch the video where I explain it to make sure you understand how to solve equations with negative exponents.

[@hqs9585]

Problem 25 . I cannot follow you! and i know the subject. this is how you do this problem:log in base 4 of 16 is N , the exponent needed to raise 4 to obtain 16 which is 2. second term N is exponent needed to raise 2 to obtain 16 which is 4, then 6*2 - 4 = 8

[@StudsMac]

For question 24 shouldn’t there be a right angle symbol or explanation in either the diagram or the text? Otherwise you are just assuming that it is a right angle (even if it is drawn to scale)

[@preppros]

Good catch! Yes, on the ACT you should never assume a triangle is a right triangle. I should had added a right triangle symbol or said right triangle in the question.

[@senpie2865]

isnt number 5 answer supposed to be letter D? because it says -1/4 but you didnt put the - sign?

[@preppros]

No, the video is correct. The solve for x, we add 1/4 to both sides.

[@senpie2865]

@@preppros oh okay, thank you for responding. i was a bit confused

[@konai1156]

Question 10, I didn’t understand it

[@MOHANNADBASELZIDANElMASRY]

is this act subject test or normal act

[@preppros]

This is the normal ACT.

[@jonaygrey2911]

I really need your help I wanna improve my act score to get an 18 in ela and 19 in math what book should I use to retake the practice test around September in 2 more months or around the end of December I am really bad at math and have a time in rm the formula for math should I get the 2023 2024 practice act book to study or still use my 2022 2023 book to study I feel that they updated the test version for 2023 2024 my school gave me the 2022 2023 version though I really need help and just wanna do better to get a lil higher especially on paper testing

[@preppros]

The 2022-2023 version is fine. The new book is pretty much the exact same and includes many of the same practice tests. The new book might have 1 new practice test but that's it. Those ACT books are good to use for practice tests, but you cannot get prepared just with the practice tests, as they don't actually teach you the content. To improve the math, get a copy of the PrepPros Complete Guide to ACT Math (my math book) and start with the level 1 study guide. The book has a 4 level system and study guides to make it easy to use for students of all levels. As you improve, you can move onto level 2 topics. I'd recommend signing up for the video course as well. Sign up for the free trial first (link here: www.preppros.io/act-math-course) to see how you like the course! English is far easier to improve once you learn the grammar rules. Moving your score from 18 to 25+ is very realistic. The problem is you never get taught the grammar rules at school. You can learn some for free from me in the Ultimate ACT Course Free Trial here: www.preppros.io/act-course. If you really want to boost you English, definitely sign up for the full course.

[@NathalieFlores-e5e]

At 4:41 can you explain the process of going from 23/12 to 1 11/12? I know what it is but I just don't know the steps of getting that version????

[@preppros]

Sure. 23/12 can be split to 12/12 + 11/12. 12/12 is equal to 1, so 23/12 simplifies to 1 and 11/12.

[@haninomar918]

This for M1 or M2 , because we don't have matrices in M1

[@preppros]

Neither. This is for the math section of the ACT Test that students take for applying to schools in the US. I believe that you are referring to the ACT math subject tests.

[@haninomar918]

@@preppros ok ok now I understand it , there are similar subjects in both

[@gabyvazquez3139]

Number 3 how I the sum equal to 9 when the sum answer is 16

[@preppros]

The average is equal to 9, not the sum. For 4 numbers to have an average of 9, the sum of all 4 numbers must add up to 36. So the answer of 16 is found by subtracting the other numbers from 36.

[@GhostGhost-tx5bz]

Hello PrepPros, My daughter is headed to the 7th grade in a few months and I would like for her to get a head start on ACT prep. Do you have any tools to assist with a middle schooler preparing for ACT or should I wait until at least freshman year of high school?

[@preppros]

I would not recommend starting ACT Prep until sophomore year at earliest. Starting before is just unnecessary given that students are still learning concepts in school that are tested on the ACT. There is no need to prepare for the ACT for multiple years in my opinion. Most students only need 3-6 months to prepare for and take the ACT. For now, just have your students focus on academics, building up his or her reading comprehensions and math skills and general study skills.

[@BraydenEasterling-uu8nr]

I am having trouble finding this practice test on your website. Is this test a part of your free trial plan?

[@preppros]

Yes, it is available in the free trial to the Ultimate ACT Course.

[@monicavargas9063]

Hey, for question 52 you said we could use our calculators to get the answer. I have a Ti-84 plus, I tried attempting your method of writing the fraction and then doing MATH and then FRAC, but it keeps telling me there's an error. I'm unsure if I'm doing something wrong. Could you help me?

[@Caroline-ih7hm]

You have to enter it as a division problem rather than using "alpha" like you usually would to enter a fraction. So it would be entered as 2/(1+3i), enter it, then convert it to fraction form. Hope that helps!

[@aub2540]

On 54 why do you only subtract 1 instead of 2 from the first fractions?

[@preppros]

When you are selecting the probability of the second person, there is only 1 person less to select from for both that age group and the total (since the first person has already been selected), so the numbers decrease by 1 in the numerator and denominator.

[@swh0812]

Question 36 the answer is 6, not -6. You cannot have a negative number of hats...

[@preppros]

Yes, of course! I mistakenly did not cancel out the negative signs and wrote -6 instead of 6. Good catch.

[@wendytk3469]

i dont get question 10

[@fatmamousa2128]

Which ACT is this 1 or 2 and math 1 or 2

[@preppros]

This is for the math sections of the regular ACT, which students take for their applications to US Universities. The regular ACT has sections for English, Math, Reading, and Science. This is not for the subject test ACTs that international students take (I believe those are the math 1 and 2 that you were referring to).

[@kourondareallegend5891]

I dont feel you really explained 52 right I have a ti 84 calculator and when I put in 2 over (1+ 3i) it said error, or just gave me the same thing I put in right back.

[@preppros]

It works in TI-84 calculators for sure! If it is not working in yours, you must somehow be entering it wrong (it if says errors, it's possible you did not put a parentheses or something else) or there is something wrong in your settings.

[@Bluphoriia]

do you have some sort of live session or a way i can pay you to tutor me

[@preppros]

Yes, my Ultimate ACT Course is a self-paced online video course in which I will teach you for everything on the ACT. It's only $99/month. You can check it out here (there's a free trial too): www.preppros.io/act-course. I also offer live private tutoring, which you can learn more about and sign up for on our website as well: www.preppros.io/private-tutoring.

[@ilmakifayatullahmasud7497]

Which ACT form is this??

[@preppros]

None. It's a practice ACT that I wrote to look/feel exactly like the real ACT.

[@وفاءهاشم-ض1ه]

so i was sloving another exam and my grader was around 29-31 then i solve this exam and my grade is 27 so is this test harder than the real test or i have to study again.

[@preppros]

It'd likely be best to study more. Use this test along with the diagnostic sheet to determine what concepts you need to learn or review to be better prepared.

[@markelkelly3144]

On Question 39, I don’t understand how u could just multiply the remaining 3/7 with 3/10

[@preppros]

Since 4/7 of the audience members drove a car, 3/7 took another type of transport. The question tell us that 3/10 of the remaining audience members rode a bicycle. So, 3/10 of the people remaining, which is 3/7 of the total, rode a bicycle. To find 3/10ths of the 3/7, we multiply to get 9/70.

[@xJossy1]

Jesus loves you all so much and He died for you. Believe in Him and you will be saved. Good works don’t save but we still do good works as Christians because we follow Jesus and not this world. Repent of your sins!

[@DepthUnchecked]

I am Jesus

[@f4ephilosophy691]

I am god, you may tell me your sins and I will forgive them, however I first need the 16 digits of your credit card and the 3 funny numbers on the back.

[@lureliapacheco4531]

Hello We are not available to use calculator

[@preppros]

On the ACT, a calculator is allowed.

[@danjohnson889]

Man my trainer told me I was doing an 3 hour math test and I get to the testing site. ACT test waiting for me. Scored a 3 , 4, 4 for a broze badge. I really wanna retest.

[@jakob9111]

You scored a 3?

[@MidhaaTahani]

For question 3, isn't the answer 16?

[@preppros]

No, the explanation and answer in the video is correct.

[@MidhaaTahani]

Oh, I'm sorry. I'm an 8th grader. I still don't understand it properly though.

[@quilendyeugene5010]

on number 35 , you stated that after squaring 3 it equals 9 & after squaring 5 it equals 5?? a little confused on that part .

[@preppros]

When you square a square root, you just get the number. So on 35, when I squared root 5, it turns into 5.

[@eddieprice4974]

I cannot find the link to this exact test, can you post that?

[@preppros]

Download This Full Practice ACT Math Test Here: www.preppros.io/act-course. Once you join the free trial (no credit card needed), scroll to the bottom to find the free download of this test.

[@eddieprice4974]

@@preppros when doing this, only the full curriculum shows, not the download

[@preppros]

​@@eddieprice4974 You have to get signed up to enroll in the free trial. The test is then in the lecture titled "PrepPros Practice ACT Math Test (PDF Download)." Click on that lecture then you can download it. It sounds like you didn't actually sign up.

[@eddieprice4974]

@@preppros thank you so much, I see it now!

[@nayeemahmadxt7043]

Did the act full pratice test come out for the 2023/2024 act testing

[@preppros]

If you are referring to the 2023/2024 Preparing for the ACT Guide, which has a practice ACT, this has not been released. However, the test in that guide is always an old practice test from an officially released test date. The ACT releases practice tests for the April, June, and December test dates each year, so the April and June tests have been released for 2023. However, the ACT is very aggressive about their copyrighted materials so I am not allowed to show those tests on KZbin. This test is one that I have written that accurately reflects the questions on the ACT and difficulty of tests in 2023.

[@Bluphoriia]

@@prepprosdo you have any for 2024?

[@DreasTapes]

I take the test in 2 hours, I’m cooked

[@nhmk2355]

17:38 ay

[@nhmk2355]

Matricies System of equations Quadratic formula Vectors i=x Ratios rates percents

[@nhmk2355]

Logarithms Exponent rules

[@nhmk2355]

Probability

[@zoeewewq5180]

can i buy the book as a pdf?

[@preppros]

Yes, you can buy a PDF version of the book here: preppros.teachable.com/p/my-downloadable-80683

[@zoeewewq5180]

@@preppros thank you! just bought it right now waiting for the gmail

[@maranathaestanus4586]

you go to fast

[@hqs9585]

Problem 19: no need to do calculation . It is obvious that perimeter ha to be more that (18+4)*2) =44, Only choice is 48. Please do not complicate this exercises.

[@preppros]

That's a great shortcut for stronger math students like you. Many students do not realize that shortcut method, so knowing how to solve this algebraically is helpful not only for this question but for others as well that test similar concepts.

[@hqs9585]

Problem 29, terrible explanation sorry. It is a permutation problem 3 choices out of 23 and 2n choices out of 8, 3P23, and 2P8. (sorry about the format of the typing) nPm is just = m!/(m-n)! , that is all so 23!/20! =(23)(22)(21), and 8!/6! = (8)(7).

[@hqs9585]

Problem 55: WRONG the c orrect answer is 113.86, you made the silly mistake using your calculator, you divided and then multiply answer by 1.2 instead of dividing, calculator usage ERROR, NOT the expression written, be more careful buddy.

[@preppros]

Yes, you are correct. There is an error in the video and the answer to 55 is C. Good catch! That's why you should always double-check your work if you have time (and of course not be talking the whole time while solving questions).