Proportion word problem (example 2) | 7th grade | Khan Academy

Mika can eat 21 hot dogs in 66 minutes. She wants to know how many minutes it would take her to eat 35 hot dogs if she can keep up the same pace.

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[nocturnalvisionmusic]

0:17 "I have to remove a hair from my tongue"

Khan don't stop getting better and better 😁😆🤣

[ashleybaird]

My class does this differently... we divide h(right)/h(left) to find the scale factor and then multiply m(left) by the scale factor to get m(right).

[Michaela-yhsm]

"I have to remove a hair from my tounge" XD

[aishwaryasridhar]

Sal: Doing a whole amazing problem!

Me: CrOsS mULtiPLy AnD DiviDe

[wadada]

They way i got it was to find out how many minutes it took her to eat one hot dog. So i divide 66/21 which is 3.14 so i times that by 35 which give me 109.9 so i round it to 110.

[kartheekdavid]

The way he did this was very stretched out. Multiply two proportions using the butterfly method. If you have two proportions, multiply top left by bottom right (Then place to left side of equation, most likely going to have a variable), then multiply bottom left to top right. Very easy. It could've came out with the outcome 21m=2310 (I got 2310 because I multipled 35 and 66 together using the butterfly method I explained) and once you get that outcome divide 21m by 21m so they cancel out, and then divide 2310 by 21 getting the answer.

[fnggamer]

Thanks dude this really helped for my test

[suhakamal]

I’m 11 and I watch these videos I love these videos

[raregem]

All this is unnecessary....Cross multiply 66 x 35= 2310 and divide 21. M = 110.

[lukeqiao]

can you cross-multiply to solve for m?

[a.nnyyaaaa]

Nothing changed i still don’t get math proportions
Like if you agree

[aildana]

So if you guys get really confused what the heck he is saying, there is a way easier way to do this. Multiply 66 x 35 which would equal 2310 then you want to divide 2310 by 21 then you will get the same exact answer like he did which is 110. Comment or like if this was helpful!😁

[umakumaravel]

You could have cross multiplied to get 21m = 35x66 and m = 35/21 x 66 to get m= 110 1:00 but still great vid bro,

[martinezcarlos]

You can also cross multiply and then the number with the variable next to it is your be your denominator(just write the number) and your gonna do the same with the product with the other numbers that have been multiplied. After that it's gonna be "the product divided by the number (the one paired with the variable, don't add the variable in the denominator) and you get your answer

[bushratahir]

21/66 = 35/x

21x = 2310

=110

you're welcome.

[manglestarr]

why are some of you people so rude if you don't have something nice to say then DONT WACH THE VIDEO

[MrAnkittechnical]

Method is quite nice but not faster then other method because very durable.

[cameronjones]

bruh maths is amazing that bit where you cancelled out the 7 from 5*7 and 3*7

[medhasarker]

Why do u gotta complicate things. U could have just done 35 x 66 divided by 21 which equals 110. I did that in 30 secs while u did this complicated thing in 2 mins. Im not hating tho im just saying cuz it can confuse people

[KingMaker]

Why you calculate in difficult manner look here 66/21=3.142, 3.142*35=110 simple