A car travels 20% faster than a truck, if the car’s speed is 80 mph, what’s the truck’s speed?

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[@StreakingTiger]

66.6 is a Devil of a speed to travel.

[@RobertSkene-qw3ob]

The car is speeding and the truck is not! So the car will get a ticket 🤣🇨🇦

[@v.c.g3246]

I did a "rule of three", so I dont know if it counts, but it worked! 😂 This is what I did: car speed= 120% (100 truck + 20 car) , so if car speed is 120% = 80 mph, the truck speed is 100%, what's the cars speed.? 80 x 100= 800/120 = 66.66

[@Surreal_Wizard]

Get your kicks driving sixty-six point six!

[@russelllomando8460]

on Route 66

[@BradTheProducer]

15:43 - An F at the top of my math quiz...that brings back memories.

[@kevinmadden1645]

Don't brag!

[@ResourcefulNomad]

80 MPH = 1.20 x Speed of truck 80 / 1.20 = 67 MPH

[@SandraDevant]

I like your style straight to the point

[@russe19642]

You formulated better than his original question,he makes you concentrate on the cars speed.

[@martinbrenner6664]

Where did you get the 1.20 from? I can’t see the original problem now. Is that supposed to represent 20%?

[@ResourcefulNomad]

@@martinbrenner6664 the car is traveling 1.2 times or 120% faster than the truck.

[@Pax.Alotin]

@@martinbrenner6664 It represents the percentile difference = being 20% --- Think of 1.20 as being a 'shorthand' representation of the same thing. 🙂

[@oldfart3539]

Easy. Car Speed (CS) is Truck Speed (TS) plus 20% of TS. CS = 1.2 TS. So, TS = CS/1.2 = 80/1.2 = 66.66

[@oastie3]

I always told my children that to successfully complete a maths problem, first you needed English. In other words you needed to understand the problem, as you indicate with your advice to read it three times.

[@JosephWood1941-iz6mi]

66.666 recurring. Good mental arithmetic practice.

[@taylormatthews3767]

I wish I could do mental arithmetic like this

[@JosephWood1941-iz6mi]

@taylormatthews3767 First of all, read the question carefully. Sometimes it helps to say it out loud. It provides aural feedback that reinforces the brain's internal ones. Then, analyse the question. In this case, start by considering what the first sentence means. 20% faster means that the car is travelling at the truck's speed plus 0.2 times the truck's speed. So that is therefore 1.2 times the truck's speed. Now we need some basic algebra. Let's call the truck's speed T. 80 = T × 1.2 Therefore, 80 ÷ 1.2 = T You can now divide 80 by 1.2 to get the truck's speed. But there's a quicker way. Both 80 and 1.2 are divisible by 4. So, doing that, you finish up with 20 ÷ 0.3. Now, 20 ÷ 3 is 6 remainder 2, so that's 6.666.... But, 3 is 10 times greater than 0.3, so you need to multiply 6.666.... by 10, giving us 66.6666... mph. Final check- does 66.666mph make sense? Yes it does. I'm good at mathematics, but I'm useless at teaching. Too impatient. But that's how my mind worked on this problem I find that mental arithmetic works better for me if I visualise the actual numbers and equations in my mind. I close my eyes and see "80", for instance. We all have our own talents. Mine is boredom, but your's are probably much more interesting.

[@thinkcivil1627]

Here is the frustrating part. Back 40 plus years ago, that was not how we set that formula up. That's why parents always have trouble helping their kids with math. They see the teacher at school putting it into a formula that the parent wasn't using (nor the world) for a long time before someone thought new math was needed. I sure hope that they haven't changed quadratics.

[@virgeliotudtud3125]

Let x = the truck's speed, x + 0.20X = 80, 1.2x = 80, x = 80/1.2 = 66.7 is the truck's speed, simply put. To check your answer 80 - 66.7 = 13.3 ; THEREFORE 13.3/66.7 = 19.94%

[@vespa2860]

Car speed/truck speed =120% 80 mph/ T speed = 120/100 Cross multiply 80*100 = 120* T 8000 = 120 T 8000/120 = T T = 66.66... T = 66 2/3 mph

[@cougar02000]

That maths problem is very easy to solve with very little working out, just divide 80Mph by 1.2 to get 66.666Mph or to round it off 66.7Mph.

[@AnthonyMartinez-fx8pr]

People are saying 64 because 20% of 80 is 16 which is how much faster the car is traveling than the truck. Take that from the original speed and you get 64.

[@Serisky621]

No, the difference, or how much faster, is 20% of the truck speed, which is less than car speed of 80 mph. This 20% is therefore less than 16.

[@AnthonyMartinez-fx8pr]

@@Serisky621 As I said " that is why people are saying 64." I didn't say anything about wrong or right.

[@sudsfour4553]

Which gives you the wrong answer

[@AnthonyMartinez-fx8pr]

@@sudsfour4553 You obviously didn't follow the conversation. The question many were asking is why so many people were saying 64. Start with the video and follow the comments.

[@Canoga_Knuckles]

Bingo

[@CorletteViljoen]

X = 80 x (100/120) = 66.7 Basic accounting formulae to get x before % added

[@benicamenica1557]

Was never good at math...even one plus one was a struggle.... But...so long as I can count $20's, $50's and $100's......

[@danmike2305]

Nice word math problem.

[@donttellmeitsraining8160]

So, how far apart will the truck and car be after 24 hours?

[@terry_willis]

d) 66.667 mph

[@davenoejoe]

I'm glad you are not my math teacher. I would totally fail if I relied on your advice. Don't need to hurt your feelings but you complicate the simple.

[@antoniobragancamartins3165]

​@@davenoejoeyou must return to elementary school. The guy is right

[@antoniobragancamartins3165]

The only one right

[@perro0076]

I'm really crap at this, but i like the first way to solve this. The second way, to me, has an element of judgement. Why can't 80 be the 100% figure? Obviously i wouldn't go back and work backwards to double-check my answer.

[@dazartingstall6680]

The truck's speed is 100% of the truck's speed. Let's call that x The car's speed, 80 mph, is x plus 20% of x. Which makes the car's speed 120% of x. That's why 80 isn't the 100% figure.

[@russelllomando8460]

got it 66.7 used brute force and the formula thanks for the fun.

[@alvingoodman6539]

I like to say that the truck is going 20% slower than the car. So , 80 x .2= 16. And 80-16= 64. Let’s test it with two vehicles. You drive the lead car and drive 80. I’ll drive the trailing vehicle at 64 mph. The speed limit is 65 nd there is a cop. Which one of us will get where we re going first? And who gets the ticket?

[@durrrrl3435]

You will get to where you’re going first because I will be pulled over getting a ticket!😂

[@mikeransom1168]

I divided 80/6X5=66.6666... What this did was give 20% of truck speed and you multiply that by 5 to get truck speed

[@MGDLProductions]

I used brute force. Started with a figure lower than 80. And understand that 20% of something is to add 1 to the percentage (hence 1,2) I took 62, 62 x 1,2 =74,4. I must have a bigger number I took 65, 65 x 1,2= 78, near, maybe 67? 67 x 1,2 = 80,4, hmm maybe 66,5? 66,5 x 1,2 = 79,8. 66,7? 66,7 x 1,2 = 80,04, Yeah... Then I realized that I had the answer 80/1,2 = 66,6666 Now I will remember that when something is a percentage bigger than something else. deduct the something from 200 (as a decimal) and divide the something else with that and you got the answer. 200-80=120 (as a decimal = 1,2) then 80/1,2 = 66,6666 200 only apply as long as the percentage is less than 1, else 300 and so on..

[@dannygjk]

Yeah percentages can confuse people. Ask a person to increase a number by 50%. Then ask them to decrease the resulting number by 50%.

[@Pax.Alotin]

Try that with Zero ---- Or as in the words of the famous song ----- Nothing from nothing - leads to nothing'

[@argonwheatbelly637]

@@Pax.Alotin : 75% of nothing is nothing.

[@Serisky621]

The result would be much less than original number, if original is positive. For example, 100 + 50% =150 150 - 50% = 75

[@legion162]

66mph is close enough, you will never be able to read 66.66.. mph on the truck speedo

[@Ayelmar]

solved at the thumbnail, I'm getting the truck going 66.66 mph. Let x = the speed of the truck. 1.2x = the speed of the car. 1.2x = 80 x = 80 / 1.2 x = 66.6666666666666666...

[@thinkcivil1627]

That is how we were taught to set up the formula in school. The "new math" rules my daughters came home with made me wonder why in the world would they complicate something that is already complicated to most people.

[@thebeerinnandrewmckenna2655]

I did it like this, 80/4 is the 20%, so took the 4 from 80mph, and equalling 76

[@chrisbyrne5678]

80 mph divided by 12 will give 10% of the trucks speed (6.66 mph), then multiply by 10 to give 100% of the trucks speed = 66.66 mph

[@jeremyashford2145]

Sometimes with these puzzles we are tempted to come up with tidy looking answers, so I suspect that you were seduced by your own neatness. The real answer is anything but neat (so while it was my answer I did feel the need to double check to commit to it), but it is manageable.

[@roberttrough6439]

64 mph truck speed

[@martinbrenner6664]

64mph

[@lazarorosenberg7795]

is it 64mph?

[@mikesteffes9999]

If you see a TRUCK traveling a US Interstate at anything less than 75, you’ve seen a unicorn…

[@StreakingTiger]

Actually SWIFT trucks always do not speed faster than the posted limits. At least, that is my experience. They are the ONLY truckers that I know exactly what they will do at all times.

[@devonwilson5776]

Greetings. The answer should be 66.6 MPH. We determined the answer as follows. Let the speed of the truck be X MPH, then the speed of the car is X+20X/100 and since we are told that the speed of the car is 80 MPH, we have X+X/5=80 MPH, and 5X+X=400, multiplying throughout by 5. Moving forward, 6X=400, and 3X=200 MPH. We will now divide throughout by 3 to get X, the speed of the truck to be 66.6666 which gives the approximate value as 67 MPH.

[@Patriot_Drone_Services]

I guess I’m mathematically challenged… My formula is not in algebra. The question is determining the speed of the truck, based on two known numbers, the speed of the car at 80MPH, the car is traveling 20% faster than the truck. So what is 20% of 80? A: 16 (or 16 MPH). So a theoretically logical equation if 20% of 80 is 16, is to subtract 16 - 80 = 64… and that folks is why I am not a rocket scientist!

[@user-vg6pr5yv6s]

64 MPH

[@thego-o-dstuff1036]

80/120×100 = 66 and two thirds.

[@jamesmatheson5115]

So we have a problem that cannot be resolved, great, its not a huge problem if you are only going to travel for a couple of hundred miles, but if we ever get into space travel and we are talking light years, now we have a problem.

[@NN_Prod]

64mph?

[@rossbatrossbdotcom]

that's what you get when you incorrectly subtract 20% of 80

[@johnpoole6711]

66.666

[@trevaperes5343]

64 mph

[@mikeorgan1993]

Wrong

[@samwilson2797]

Right

[@ralphcloar4009]

96 MPH

[@luillierstephane1463]

I'd say around 66.67mph

[@stevewthespider]

the truck is going sixty-six and two thirds miles per hour

[@dannygjk]

Some people will have a religious mental block to solving this.

[@dazartingstall6680]

It took me far too long to get this joke.

[@subasu478]

66.6

[@mikewarren9850]

Truck traveling at 64 mph.

[@mikeorgan1993]

I really don't understand why this is so difficult for some people. For me this is a simple problem that has everyday use. I think it might be something I realised when my kids were in school. They were given homework and asked me to help. Of course I was not going to do it for them so I asked them how they were taught and what they showed me made zero sense. First mathematics is logical and so when you put things on paper neatness is important, they had never been taught that simple skill. I had to teach hem to keep things in columns. The bizarre methods they taught made zero sense. The issue for me is there is no new way to teach maths its been the same for over 300 years so why do trendy teachers think they can change something that does not need to change. As they say if its not broken why fix it. I have seen new engineers coming into my profession who create over complicated solutions to problems that have already been solved. I can only blame bad teaching. This problem is almost instantly solvable. The car is traveling at 120% the speed of the Truck so take the speed of the car divide by 120 then times by 100 problem solved and frankly you should be able to do that without a pen and paper. Oh and my kids all got A+ in A levels (English higher Certificates) because I told them to ignore the idiot teacher and I taught them. They had to, if they didn't, their mother who has two degrees in Accountancy and Interpretation would have been very disappointed in them, she was doing advanced calculus at 15 in Russia whilst I had to go to Uni to get that far..

[@ianmorrison6798]

The car is travelling 120% of the trucks speed at 80mph. Just divide 80 by 120 and multiply by 100 =66.66666667. OR 80/120 = 2/3 = 66.66666667. Understanding the question first is the key, that's why It was called the 3 R's at school...Reading, wRiting and aRithmetic. 😊

[@scimitar415]

were you ever a tobacco auctioneer?

[@melvinkaufman9114]

60mph.

[@b213videoz]

5:23 still no explanation as to why that approach didn't work. Normally it works.

[@weenercatotto]

Whenever I see 20%, I see 1/5. So, 80 mph is 1/5 more than x. Divide 80 by 6, and then multiply the dividend 5. 66.6⁶6666

[@Eyes-of-Horus]

How fast is the truck going? Don't need math to figure that out. It's 65 (on the speedometer and they're always slightly off) because that's the speed limit and the car will get pulled over for speeding in about a mile down the road.

[@kevingeier3385]

The truck speed is 80/120×100 equals 66.67 miles per hour

[@taebkim1]

X * 1.2 = 80, X = 80/1.2=66.67

[@garybird4992]

The car is going 20 % faster so its 120 of the truck speed 80/120 × 100 = 66.66 recurring.

[@saeedmemon2622]

The mathematical answer is about 66.666. since it's not possible to drive digitally, so by maths principles truck can be driven at 67 mph speed.

[@antonydewar7875]

And that took over 15 minutes to explain. Jesus wept. How to turn people off mathematics in one easy lesson.

[@argonwheatbelly637]

Jesus wept over the number of people who answered, "64."

[@mytube082007]

Truck speed is x x + 0.2x = 80 (Car's speed) x = 80/1.2 = 66.6666

[@tomtke7351]

two equations two unknowns unknowns: C : car speed T : truck speed equations: eq.1 C = 80mph eq.2 C = T(1+20%) sub eq.1 into eq.2 80mph = T(1+20%) 80mph/(1.2) = T T = 66.67mph

[@BliSte-gr4lt]

Why do we need to take 20% of 64mph (6 min into video)?

[@Syngynn]

0 MPH he's parked at the diner.

[@dougyoung8773]

We're starting with 120%=80 and looking fir the100% value if 120%=80. So looks to me like 1.2x=80 Then x= 80÷1.2 perhaps I made an error. But I see 66.7. Cause 20% of 80 is not 20. But 80% of 80 would be .8×80 which would be 64. Wierd. But were not looking for 80% of 80 were starting at 120% =80, and looking for the number that would be the 100% value which would be 80÷1.2 =66.7 so I did it right in the first place. But allowed some getting an even number answer to question my original answer. Well I'm nearly 80 and have had 2 strokes so sometimes things that seem neater, seem more like what people often try to make such problems come out, so I let people getting 64 cause me to question my original answer. But it is it seems basically an endless string of 6's with 2 digits before the decimal and more after. and rounding off to 66.7, or 67 or 66.67 would be based on how many significant digits one could count as reasonable. But 66 2/3 also sounds good to me.

[@williamfowles2940]

Similarly the video could have over 80% sooner if you eliminate all the faff and constant repetition! If you're telling us you're going to 'go ahead' and do something please 'go ahead' and do it!

[@josephlaura7387]

66.67mph

[@DarrenBarstad-ng8tu]

The car is driving 80 mph, doesn't say it's driving 80.04 mph. So that's not the correct answer. Got me more confused!

[@eatyourpants3947]

It is the correct answer, the .7 is rounded, really it's 66.666666 with the 6's repeating forever and with each 6, it is closer to 80, 66.7 is just an approximation

[@pmwkiy6879]

Speed of car 80mph! Speed of truck 66.667mph. If the speed of car at 80 mph is 20 percent faster than the truck, then 80 mph represents 120% So 100% of 80mph =(80÷120) × 100 = 66.667mph Speed of truck = 66.667mph To verify answer back to speed of car: Speed of car at 120 % of speed of truck (66.667mph): = (66.667 ÷100) x 120 =.66667 x 120 =80.000mph Or 66.667 x 1.2 = 80. 000mph 🙏

[@marthacalkins8054]

20% is 1/5th of 100%. 100% + 20% = 120%. 20% is 1/6th of 120%, which is the car’s speed, which is 80 mph. Truck’s speed is then 5/6th of the car’s speed, which is 66.6666…7

[@komiczar]

I like your processing Thank you.

[@lazecowboy]

55 the truck is doing the speed limit.

[@girmaybass68]

This is what I did before watching video. Car speed = 80mph=X. Truck speed 80mph minus 0.2X. What is 0.2x of 80=16. Truck is driving 64Mph. Hope I am right!

[@jamesjackson189]

Yes I subtracted 20% from 80 is 16. The answer should be 64

[@everettcalhoun8197]

But if the truck is going 64 then 20% faster is 76.8 mph which is not 80 mph. The answer is approximately 66.666666 repeating.

[@Serisky621]

​You fell into a common math trap. The difference in speed is 20% of smaller (truck) speed, NOT 20% of larger (car) speed.

[@user-se8ds5ev5k]

60 mph

[@alanpeachey4085]

196. That’s the speed we got under going twenty per cent Of Eighty Is sixteen The car is faster Not Slower

[@arrowbosmith]

I just divide 80 by 6.

[@seibertmccormick184]

I get 66,6667 MPH

[@scouser2230]

66.67 mph.

[@user-ve5ix1ns9u]

The truck is speeding.. Should be limited to 56mph!!!

[@stevenfredell1115]

66.666mph x×1.2=80

[@berniefynn6623]

96mph

[@russelldykstra236]

Can't hear you even at ful volume

[@user-oh2hs6jh5x]

66.67

[@volta2aire]

66.66 mph

[@johansteyn8526]

66.7 mph

[@argonwheatbelly637]

People!!!! "20% faster" means 100% + 20% = 120%. The ones who are coming up with 64 think that the car is at 100%, so they subtract 20% from that to get 80%. No!!! Stop that!!! That's not how it works. No matter how you slice it, and I haven't the time to explain more than this, tonight, the answer is still 66⅔.

[@dougyoung8773]

Having put a lot if barly n hops in my belly over the past .78 century, creating a far less rare gas, I agree with you. But I gotta go sleep too.

[@fenderbenderxaddo5974]

Took me a minute 80 divided by 1.2

[@brianndrelan135]

80÷1.2= 66.67mph

[@rogersmith5870]

80 x .8

[@evenberg8499]

...and I who wanted to be a certified professional expert of high degree excellence.

[@Jeanne90275]

66mph?

[@berniefynn6623]

16 mph

[@CHThornton]

96 mph.

[@argonwheatbelly637]

66⅔ mph. Took a few seconds. 20% = ⅕ more, so the car is going 6/5 of the truck. The truck is going ⅚ of the car. 80×⅚=66⅔. That's how I did it. However, the correct way is to set it up algebraically, like in other replies. I simply shortcut the process.

[@juliehalligan6534]

66 m/h

[@bobegan2121]

That’s 66.6 plus 2 times 6.66.

[@chucksteele4787]

66.66

[@christophermcbride1738]

66mph

[@martinbrenner6664]

I knew I was wrong, but I wanted to be first.😅

[@samwilson2797]

You win!!!!

[@antoniobragancamartins3165]

In 5 second: 66.666km/h

[@dazartingstall6680]

80/120 × 100 = 66.67 mph

[@mikeorgan1993]

As simple as that. Did you do it in your head? I did but then as an Engineer I am used to it.

[@dazartingstall6680]

@@mikeorgan1993 Yep. 80/120 finds you your 1%, then multiply by 100 to get the whole.

[@mikeorgan1993]

@@dazartingstall6680 I know I have been doing this type of calculation for over 57 years since I was 11. What I asked you was did you do it in your head or did you need a calculator/pen paper? That fact it was a 120/80 ration made it far too easy but it demonstrates the principle.

[@dazartingstall6680]

@@mikeorgan1993 Oops sorry. I didn't notice I hadn't answered your actual question. Yeah, as you say this on'e is easy, 'because the fraction is just 2/3 which we all know is 0.666...

[@mikeorgan1993]

@@dazartingstall6680 Thank you, so I am assuming you are over 50 or you had an old fashioned teacher because many young people who went to school in the 80's and after just don't seem to be able to get their heads around fairly simple concepts. I am assuming humans are not regressing in intelligence so it must be the schools. My wife is Russian we met in Siberia she was doing university level maths in what in England we would call the old 5th year which is now in the UK Year 11 and the US Grade 10. Her maths is so good even today she is faster than me even on complicated calculations and when you consider she was an Accountant and I am an Engineer I should be better. Maths skills are vital at an early age if they are not taught properly the child may never be able to recover. When you consider Maths is the only discipline that is truly universal its appalling our schools are failing children so badly.

[@arthurtafero9230]

Hi, if the car is going 80 and 20%of 80 is 16, then why isnt the answer 64?

[@margaretjordan5381]

I still don't understand how you divide 1.2 into 80.

[@dazartingstall6680]

Move the decimal point in 1.2 one place to the right, to make a whole number. Divide 80 by 12. That results in 6.66.. then move the decimal point one place to the left, which gets us 0.666...