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.

[@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 :)

[@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! 🙏🏼

[@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.

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 : )

[@spankmobley]

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?

[@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

[@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!

[@MultiDrGh]

lemona cars are awesome!

[@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.

[@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 👍

[@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?!?!?!🤩🤩🤩☺☺☺

[@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.

[@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.

[@seanchow1999]

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

[@ashenafinuguse6671]

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

[@BreathingInPixels]

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

[@marcoglara2012]

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

[@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

[@amrmagdy5041]

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

[@sheikhberyal3290]

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

[@ancavaida7481]

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

[@some_random1835]

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

[@rituponphukon860]

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

[@changgiljang4660]

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

[@hdela8172]

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

[@maureenobando4956]

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

[@omom4248]

You gorgeous 🎉

[@yt_bharat]

Excellent teacher and superb communication

[@jordanj7590]

your pictures and humor help immensely !

[@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?

[@TheSmilingali]

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

[@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.

[@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.

[@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.

[@hemaupadhyay4160]

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

[@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.

[@Kwintessential2]

Very clear explanation

[@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 :)

[@amalalife1993]

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

[@sadriehgo]

Very simple and easy understanding video, thank you

[@n.s.karthik5628]

Wow, your explanation is amazing. Thank you.

[@user-ij8yu5zz6k]

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

[@omarmowafy9613]

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

[@brianaranha4870]

Really well explained and graphically represented. Kudos

[@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!

[@namratachauhan9740]

Explained very clearly and extremely helpful :) Thank you

[@danielaschalew]

you are life saver

[@sd1556]

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

[@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

[@akachimbogu2063]

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

[@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

[@niranjanwjames910]

Very clear explanation. Thank you Tyler.

[@charleshaines7820]

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

[@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

[@virtuous__woman7]

Thank you for this great explanation!

[@LegendaryX3000]

incredible and fantastic learning experience in this one video!

[@addy7464]

Very well explained.

[@daviddowner2869]

really helpful and helped me with a homework assignment thanks

[@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

[@renan6827]

Great explanation!

[@Muuip]

Excellent!Very helpful!Thank you.

[@guitarkahero4885]

Nicely explained. Thanks for your efforts.

[@dr.ankita]

Very beneficial. Thank you for posting :)

[@sciencenerd7639]

beautifully explained

[@JoshuaCB1987]

just saved my life. thanks!

[@smitchovatiya2601]

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

[@veerutekure]

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

[@TungNguyen-vl9kr]

what a very great video. thanks so much

[@FM-dy9li]

Voici les différents intervalles de catégories de poids. Here are the different ranges of weight categories. Very Light (less than 65kg (143 lbs). Light 65kg/74kg (143 lbs/163 lbs). Average weight for a man is 75kg/83kg (165/184 lbs). Light Heavy 84kg/95kg (185/210 lbs). Heavy 96kg/119kg (211/263 lbs). Super Heavy 120kg (264 lbs or up).

[@krishnahingoo2772]

you are awesome mate. thank you

[@SunilDavuluri]

Maybe I am wrong, but in your regular avg example you only took one kid and one adult and divide by 2, which is average (Sum(quantity)/count ) and weighted average you took the weight of 5 kids and one adult and divided by 6 which is also an Average. sum(quantity)/count, Not weighted average. The correct example is the percentage example wherein you are giving "Weight" to a particular subject based on importance, number of cars being the weight and hence give it a larger percentage.

[@ginjackson8092]

I love you Tyler! You make this so simple!

[@anmoljain1204]

Clearing concepts👌👌

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.

[@pratiksaha2592]

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

[@ITSMRMINE]

Bruhhh, this video must have taken pounds of time. Over the top, lezz goo

[@aakritkashyap589]

thank you sir I will be always thankful to you for showing me such a good kind of knowledge thank you and i watch your each n every vedio thank you I really appreciate you

[@AbdulQadir-gf5nv]

Thanks a lot for excellent video

[@sadhguruwisdom5846]

Excellent explanation!

[@milligangirl]

Great job Tyler DeWitt!

[@prasanraj4108]

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

[@alexrosen8762]

Great explanation! Thanks a lot :-)

[@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).

[@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?

[@dantristan8271]

Very Helpful!

[@unrealr684]

Great video! Nice explanation.

[@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.

[@laurencemoore9480]

oh my god you helped me so much thank you so much tyler xoxoxoxo

[@bilalmuhammad5112]

Such a awesome lecture much appreciate

[@bhtr100]

Excellent teaching

[@aamirmajeed8218]

fantastic ....

[@HannoWg]

That was well explained, keep up

[@devcarretero4486]

Best explanation ever!

[@ankushkachhave3484]

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

[@squidb8]

Thank You Tyler that was great stuff

[@kalki3060]

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

[@ankitamanuja3685]

Thanks 😊 you explained really good.