What is a Weighted Average?

[@tdewitt451]

Hey everyone, I'm here to help. If you have any questions or just want to learn more, click on the link in the description above. It'll take you to a page where you can ask me questions.

[@htethtet3440]

I'm so so happy and grateful for having a person who can explain Chem this easily. The school need more professors like him. Thank you so much.

[@smritimisra]

How incredibly creative and helpful! How patiently and beautifully was this explained! 🙏🏼

[@jhoysienho6850]

Thank you for showing us how to do the weighted mean. U did better than my teacher. Thanks again

[@tianova4834]

Yup thank man, I’m still sad tho cause I’m gonna fail my midterm

[@karnakmonroe5740]

@@tianova4834 I never finished high school ( got a GED) and had to teach myself algebra, geometry, trig, and finally calculus. Im an accountant now. I hope you did well.

[@kaykhinemya8086]

Absolutely, he did better than my teacher :)

[@jadeyun8149]

Average of the group at 1:35 should be ((100 * 5) + 300)/6 which is 133. Average is sum of weight divided by sample size.

I thought this was average of different groups. The average person in your first example weighs 133 pound, the average group of people weighs 200. The average car weighs 3432 pounds, whilst the average car MODEL weighs 4000 pounds. I don't get the regular average at all, there is one average, and if it's 3432 or 4000 depends on the question. Maybe Swedish uses a different definition of average, but to me, weighted average is the only average.

[@zenitsuagatsuma8898]

Same here, weighted average is the only average that i know.

[@FM-dy9li]

Déclaration très incorrect tu sais, c’est faux. You’re obviously spitting nonsense my friend average weight for a man is 75kg 165 lbs, for a woman 45kg 100 lbs. You can’t call yourself a man if you are 133 lbs, a sub man perhaps.

[@vinayabhat6006]

it is , in the "regular averag" the abundance is 50%.. thats why we multiply the sum of the observations by 1/2

[@vinayabhat6006]

ik they use similar terminology in India and therefore these AP textbooks really confuse me

[@chunshine]

I was honestly so confused when he did (100+300)/2 as the average weight. I've never seen that done.

[@yobabyyo]

Um, yeah...I've also never heard of his version of the "regular average". All he's doing with his "weighted average" is to calculate the mean. "Weighted average" means that instead of assigning the same weight to each element (by simply dividing the sum by the number of elements), you assign different weights (importances) to different elements. It ends up giving a "preference" to certain elements in the sum. For example, you might have 10 measurements of your height, but five were done using a meter stick with only tickmarks every decimeter, and five were done properly using an accurate tape measure. You might not want to throw out the five less reliable measurements, but somehow you have to give them less "weight" - so you calculate a weighted average, giving e.g. the "bad" measurements only half the weight of the good ones. What you would actually end up doing here is to count each good measurement twice, and each bad one once when calculating the sum. Then divide the sum by the number of total counts, i.e.15 in this example. It biases the mean towards the good measurements in the end....look it up on wikipedia : )

[@erinaqueen8313]

thank you so so so much! I'm taking Chemistry online on FLVS (Florida Virtual school) and the explanation was really confusing. I came to you tube as last resort and you explained it perfectly ! thank you thank you thank you!

[@jasstan180]

Hi thanks for this. In 9:14, the answer you came up with was 3432 but when I did my calculations (did it thrice just to make sure), the weighted average I came up with was 3430 pounds.

[@nedalmoheef2243]

me too bro lol :)

[@VCodeIt]

mee also

[@leeladsouza1856]

hey if the kids weigh 100 pounds each, then together the weight is 500 and then for the average, you got to add to 300 and divide by 6 - hey is that not normal average. why do you call it weighted average?

[@billiebillie678]

+Tyler DeWitt could you please answer this question? Or anyone?

[@leeladsouza1856]

cool!

[@GRIMRAJ]

these are basic so i think he should rectify it too

[@marurodriaz8412]

Absolutely agree!! Why does he start calculating the mean for the kids?

[@genfaamanfunzii2623]

The identical weight of the five kids helps to explain weighted average more easily.

[@penguinmonk7661]

I had a complete blackout when I encountered weighted average for a problem for a project on heat dissipation simulation, thank you for this brief and perfect explanation, I am up to speed again.

[@SacredMachines]

What you're calling "regular average" is the average of the averages between the two groups (kids/adult). 5 kids at 100 lbs each (500 lbs) + 1 adult at 300 lbs (300 lbs) divided by the count of individual entities (6) = 133.33.

[@fullmastrinio]

Yeah, this is a missleading video unfortunately. Perhaps he just made a mistake but he could have double checked his calculation before posting something wrong

[@sourabhchawariya6602]

Exactly

[@anmolpardeshi3138]

Isnt his “weighted average” just the simple average? And then to get the weighted average, shouldnt it be ( (5/6*100)+(1/6*100) )/2?

[@y0da._.]

This guy loki saved me life!?!?! thx dude soooo much ur a lifesaver I literally have a test coming up and I didn't understand this lesson but thanks to you know I do?!?!?!🤩🤩🤩☺☺☺

[@MultiDrGh]

lemona cars are awesome!

[@areebaejaz9498]

This is the best lesson on weighted average. I was studying borrowing costs in accounting and this made it so much easier. Thank you for this amazing explanation.

[@XMChess-bn2jl]

Excellent video. Precise and clear explanation. I especially like how you show converting % into decimals and how you split the fraction with common denominator. I needed to understand this weighted average for my work to get average cost of multiple products with different prices per each product and make the comparison with previous year's figures. Thank you 👍

[@lydiaaustin2204]

Are you going into teaching? I'm a chemistry student and your videos have given me a much deeper understanding of chemistry and pass many tests!

[@amrmagdy5041]

Great job on the material and how you explain stuff, keep up the good work Mr.Dewitt :)

[@zyambo]

Excellent explanation! Odd that some people have disliked this brilliant video.

[@ABC2691]

An amazing video. I struggled so much understanding weighted average before watching this. Thank you so much Sir :) Respect from India

[@BreathingInPixels]

This is "The best elaboration". Thanks a lot brother.

[@seanchow1999]

Well explained by using the lemonas analogy!! Mann.. He is such a genius! Clap clap clap :D

[@jordanj7590]

your pictures and humor help immensely !

[@hdela8172]

Well said! I completely understand nowTyler😁👍🏾 You are amazing man! You have a gift and you are very passionate in what you do💯

[@xochitlramirez5333]

You really helped me understand math for my accounting class. You are the first person that I have understood. Could you do any videos for math classes?

[@ashenafinuguse6671]

I was in debate with many people about weighted average !! this is exactly what I was thinking thanks a lot

[@amalalife1993]

You are a great man! Thank you 🙏🏼from Kuwait 🇰🇼

[@TheSmilingali]

Tyler you are really good. Keep it up for such a great explanation .

[@sheikhberyal3290]

You posted it on in 2012, And I'm thankful to you now in 2018 :)

[@maureenobando4956]

OMG! Thank you, simple, easy to process explanations are rare. I appreciate it!

[@omom4248]

You gorgeous 🎉

[@thilankams]

Isn’t the way how regular average calculated is bit ??? the regular average is sum of all weights divided by the number (500+300)/6 is 133. it’s same as the weighted average. 🧐🧐🧐. is both are same then 🙄

[@charleshaines7820]

I just found it strange how there are four shirtless bodybuilders surrounding a little kid.

[@stephencollins1707]

Thank you for this video!!! I am studying finance and this video is very helpful.

[@rituponphukon860]

You are my hero sir. ❤️❤️❤️❤️ From ASSAM .

[@some_random1835]

Big Thanks! My Algebra exam is tomorrow and this type of question will be on it. This helped a lot.

[@yt_bharat]

Excellent teacher and superb communication

[@marcoglara2012]

Seems like you’re referring to the Standard average calculation as the weighted average.

[@brianaranha4870]

Really well explained and graphically represented. Kudos

[@namratachauhan9740]

Explained very clearly and extremely helpful :) Thank you

[@ancavaida7481]

wish I had access to this when I was going to school (2 decades ago), life would've been a lot easier :D

[@mohammadrahmat9412]

thank you very much , saw alot of examples and videos but none of them made the concept of weight clear as much as you did cuz in some situations weight isnt given and i was wondering how to calculate but not anymore now :)

[@n.s.karthik5628]

Wow, your explanation is amazing. Thank you.

[@hemaupadhyay4160]

ur videos are awesome. Its seriously helped me a lot.thanks Tyler

[@sd1556]

love your videos, you're saving me in chemistry class. Thanks!!

[@alexkorinth6459]

I was watching this to figure out a dynamics problem, and I got whiplash when he went "And now you can calculate atomic mass" like whoa there buckaroo, that's not my department. Then I remembered this is a chemistry channel.

[@johnnylch18]

I guess I always assumed the weighted average was the way to calculate regular average 🤷‍♂️

[@SeverSava]

... all you did mate, is to calculate the regular mean. That (100+300)/2 is from nowhere and has no meaning. In the end you explained in a complicated way how to do a regular mean. ....

[@obriantguyful]

He's calculating the average weight if there was 1 kid and 1 father. (100+300)/2 = 200lbs. He didn't necessarily get it from 'nowhere'. Just using it as a simple explanation of how to calculate an average of something.

[@niranjanwjames910]

Very clear explanation. Thank you Tyler.

[@sulaimansafdar8491]

Great video.. Have a question about your example with using the percentages. To get the answer in percentage and not in pounds, do we simply divide the answer in pounds by 100 to get the percentage?

[@stellaluceat7335]

I’d really, REALLY appreciate a walk through of standard deviation done by YOU. So far, no explanation has really hit home. Please and thank you.

[@ajtrott1]

Standard deviation is just a measure of the spread of data with respect to the average value eg the average of 49,50 and 51 is 50; but the average of 1,50 and 99 is also 50. But there is much greater 'spread'/distribution of data (from the average value) for the latter! This is measured by standard deviation.

[@LegendaryX3000]

incredible and fantastic learning experience in this one video!

[@GV-gn3mj]

Hi, why there is no división with percentages and what if this does not add up 100%

[@akachimbogu2063]

thank you Tyler......you are such a good teacher

[@sadriehgo]

Very simple and easy understanding video, thank you

[@narakdk]

What happens when you both have positive and negative numbers in the rates/weights?

[@eddue12345]

so where does that leave mean, median, mode and range? "weighted average" just looks like a regular average or mean to me and what the video describes and regular average looks a lot like the median to me. im confused.

[@guitarkahero4885]

Nicely explained. Thanks for your efforts.

[@Foxhiglord]

Your perception of the 'regular average' is completely wrong... Atleast as far as I know and have learned.

[@osarhiemeniyare4678]

seriously i wonder how he came up with that he should be take this video this down

[@samanthahill4152]

@@osarhiemeniyare4678 Can you guys explain it then it the the correct way instead of just saying its wrong ? not being rude but it would help some people out.

[@mwilson9672]

Samantha Hill This is late, but the way that I learned to do averages in middle school was to add everything up and divide by the amount of things there were. I don’t know why he did 100 + 300/2 (for the kids one), because that is not what I learned as a “regular” average. I see where it comes from, but it is not correct average wise. What I would have done is added 100 + 100 + 100 + 100 + 100 + 300 /6, as he did for the “weighted” average.

[@gopeshsharma5432]

@@mwilson9672 what he meant by 100+300/2 is that, if you've 2 groups, one who's average weight is 100 pounds and another who's average weight is 300 pounds and if you're asked to find out the average weight of the two groups then you simply cannot do this 100+300/2 calculation, that would be wrong, because the number of people in each group also matters while calculating average and people commonly makes this mistake of ignoring the number of people in each group, that's why he took that example. Lastly your concept is clear. This is just to explain why he did what he did.

[@fatimapeaceful]

This is because in "rdgular average" he DOESN'T take into account the number of things. Hope this helps

[@joselene1884]

For some reason, for weighted average at my university, we have to divide by the added up percentage (100) in the last problem you showed us how to do

[@ankushkachhave3484]

Great explanation sir,will u plz make video for difference between percentage and percentile?

[@ginjackson8092]

I love you Tyler! You make this so simple!

[@kalki3060]

I have a doubt,why do we convert the percentages into decimals before multiplying them with the weight of the cars?

[@prasanrajj]

great job buddy many r getting help through ur videos bravo man

[@unrealr684]

Great video! Nice explanation.

[@ambrishbhagat]

Firstly, there is nothing called regular average. Its called simple average or just "average". Secondly, you calculated simple average by just adding weight of 1 kid + Father divided by 2. This is completely wrong. Simple average should be (100+100+100+100+100+300) / 5 which is 133.33, therefore for such examples simple average and weighted average will remain same.

[@omarmowafy9613]

bro i like your way of talking , hope i will present like you one day

[@moeShuaibi]

Thank you, you have a gift of teaching.. If Lemonas were real I'd buy you one

[@genfaamanfunzii2623]

What kind of calculator are you using because when I multiply 0.11 × 4000 I am not getting your numbers

[@moeShuaibi]

@@genfaamanfunzii2623 I think because he rounded up the numbers: • @ 6:15 the real exact answer is 3,431.8181818182, if rounded up the answer will be 3432 • @ 7:19 percentages of each group of Lemonas is rounded up/down (i.e. exact percentage of Yellow Lemonas is 72.7272727273, rounded up 73) • @ 8:55 the answer with rounded up/down percentages is 3430, he used the answer with the exact percentages (3431.18181.. , rounded up 3432) because the percentages as mensioned before are rounded up/down. Is that what confused you? Or are you confused more ? 😂

[@genfaamanfunzii2623]

@@moeShuaibi I must be doing something wrong, because I tried again and got the same number you got, I understand the concept of rounding off the number. Thanks

[@daviddowner2869]

really helpful and helped me with a homework assignment thanks

[@fugazy1127]

What does the value of weighted average tell about??

[@野生七七]

Thx a lot!!! I finally understood these topics.😆

[@nikolaihatesu]

Can someone explain why you don't divide by the number of items when working with percentages? That part is throwing me off.

[@obriantguyful]

Because division has already occurred in order to have percentages. ie. 10 people out of 100 people would be %10 of people. So if you have a shipment of cars the max amount of cars would equal %100 - all of the cars. So if there were 73 of 100 cars that would be %73 percent. 11 out of 100 cars = %11. 16 out of 100 cars = %16. the total weight of the cars have already been divided between the cars. The first example (with the cars) he divided by the total number of cars due to that being part of the necessary steps to find the weighted average. The second example the cars had already been divided by the number of cars hence the percentages - no division necessary! Hope that helps!

[@PeriMedic1]

No, it is not unique to Sweden. I spent 11 years as an algebra teacher, and I was confused by his terminology. His definition of weighted average would be what I taught as "average": you total all individuals, divide by the number of individuals, and there is your average. Your explanation matches mine. Maybe it is different at MIT, or when you are a PhD (no sarcasm intended).

[@virtuous__woman7]

Thank you for this great explanation!

[@Dragos_11]

what if I need to find how many of each should be combined to get the given weighted average? good vid though 👍

[@veerutekure]

thank you very much, contents of the video is very helpful in clearing the basics doubts.

[@niaremus]

what software do u use to make this video?

[@changgiljang4660]

I have to say "WOW", finally understand why to multiply by the percentage.

[@smitchovatiya2601]

nice use of technology I can more connect with you and your way of understanding is way to easy. thank you

[@dr.ankita]

Very beneficial. Thank you for posting :)

[@moistness482]

3:55 oh no...

[@shivanevane9662]

Will pls explain a simple and weighted average method plssss

[@profmariogutierrez]

Thank you! This is just what I needed!

[@anmoljain1204]

Clearing concepts👌👌

[@vijaykumarchillal2074]

At 9:05 you have committed mistake while calculating make that correction the answer is 3430 and it's not 3432

[@curtisshartley77]

nah ... 151,000/44 = 3431.82, so rounded it's 3432. He's correct -- y'all just forgot about rounding.

[@sadhguruwisdom5846]

Excellent explanation!

Thanks for the answer, I knew I couldn't be the only one. My guess is that he is simplifying what I (and probably you) would consider a weighted average. If you understand this, you could, with some thinking, for example calculate the average salary of men and women, taking into account their professions, and therefore showing the average gap between men and women with the same profession.

[@ashimasharma4117]

In the first example, the simple average weight should be (100+100+100+100+300)/5. Shouldn't it?

[@Muuip]

Excellent!Very helpful!Thank you.

[@harifans4429]

Thank you thank you thank you thank you, I really needed help and you helped me thanks I really appreciate more than you think

[@ankitamanuja3685]

Thanks 😊 you explained really good.

[@JoshuaCB1987]

just saved my life. thanks!

[@pratiksaha2592]

examples use by u r quite funny,interesting and INFORMATIVE thank u so much

[@Kwintessential2]

Very clear explanation

[@programmingpersistence5716]

i thought the weighted average is for when we have data values where each value has a different weight or importance?

[@programmingpersistence5716]

okay nevermind i commented too early

[@HannoWg]

That was well explained, keep up

[@healthfocusnz1724]

Great explanation!

[@lelele2289]

I think it'd be a good idea to explain why someone in real life scenario would use weighted average over regular average. Not saying it's useless just so viewers can make sense of the whole thing better.

[@marishaa]

Hey, the average weight calculation doesn't make sense to me. Since there are 5 kids at 100 pounds each, and 1 father is 300 pounds. Wouldn't the average weight be (500+300)/6=133.33 pounds?

[@joshgust32]

Weighted average is an average resulting from the multiplication of each component by a factor reflecting its importance. It's my understanding that averaging the individual items that can be grouped is not a weighted average, it's just an average of the items as opposed to an average of the groups. A weighted average is used to express that a thing is more important ("weighs more in the equation") because of some attribute. For example: CASH might be weighted as 5x and STOCK weighted as 2x against REAL ESTATE equity in a weighted average of assets for a group considering liquidity as important.

[@bilalmuhammad5112]

Such a awesome lecture much appreciate