Multiple rates word problem | Ratios, proportions, units, and rates | Pre-Algebra | Khan Academy

Sometimes you'll need to solve for multiple parts of the equation before getting at the answer. Here we solve for average speed, but first we have to determine total distance and total time.

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[wiwiparis]

Would be useful to specify the formula basics : Speed = Distance / Time or S = D / T => Therefore D = V x T and T = D / V

[susanwu]

Distance, rate, and time problems are really hard. :(

[hackedbyanasshole]

great vid and as a student in 5th it helps alot

[infamousjae]

Is there a simpler way to do this ??? I’m taking a timed test tomorrow and I won’t have time to convert time into fractions

[raven]

I just came here for school.... I won’t say this is fun but I will say this is nice 👍🏻

[arushibhargava]

I rlly think you should start a crash course!!!!

[raven]

24 divided by 8 = 3 and then 45 divide by 3 is 15 so guys that’s why it’s 15

[marycatherinehendrix]

it help me a alot so i thank you so much so now i can do it at school.

[vr-yusd]

If I don't master the pre algebra thingy I fail math and this isn't helping me at all

[leanhbangit]

i didn't get it at first but... I think I'm getting it...

[VndNvwYvvSvv]

Speed = distance / time.
Total speed St = total Dt / Tt
What is each total? Just call them T1 = D1/ S1, T2 = D2/T2. The distance each way is the same in this type of problem.

D1+ D2 = Dt, and D1=D2. Or set up a mixture table...

[nicole]

The question is saying that you went to the store and every 45 minutes, you traveled 8 mph and then it says you traveled 24 mph. It isn't the same is it?
note: yes i know that mph means miles per hour

[calikidd]

There’s got to be an easier way.

And BTW: saying I am going to the store for 45 minutes is not the same as saying it took me 45 minutes to go to the store. This is why math can be so complicated. The writers of these questions must do horrible in English class.

[Scubadog_]

Every bloody time I end up with total time divided by some fraction that isn't exactly 1 hour.

[Je]

This explanation is horrifically confusing. As always, there's more than one way to figure out a math problem. I usually love khan academy, but this sucks.

[ariellamarmon]

I'm gonna assume Umaima was on her bike.

[qinshihuang]

how do Khan Academy have 3.6M subs bro we hate school