Question

Elsa runs
3
miles in
25
minutes. At the same rate, how many miles would she run in
20
minutes?

Answer 1

Do you have any idea how to start?

Answer 2

not really

Answer 3

Okay well there's two ways to do this, but I'm pretty sure you're doing cross multiplying.

Answer 4

What you can do is set up an equation

Answer 5

You know she ran 3 miles in 25 minutes

Answer 6

yes

Answer 7

\[\frac{ 3 }{ 25 }\]

Answer 8

8.3?

Answer 9

Okay so \[\frac{ 3 }{ 25 }= \frac{ ? }{ ? }\]

Answer 10

every mile?

Answer 11

That was the other way to do it lol

Answer 12

but you're most likely doing it this way

Answer 13

So let me finish with this way and then I'll explain the second way

Answer 14

sounds good
'

Answer 15

Okay so we have the first equation

Answer 16

Do you know what goes into the second equation?

Answer 17

i dont think so

Answer 18

Okay I'll help you out with that

Answer 19

\[\frac{ 3 }{ 25 }= \frac{ x }{ 20}\]

Answer 20

You know she's running 20 minutes so you know the bottom is 20

Answer 21

got it

Answer 22

Now cross multiply

Answer 23

2.4?

Answer 24

You got it!

Answer 25

use the ratio method

Answer 26

so 2.4 miles in 20 mins right?

Answer 27

The other way was to just divide

3/25 and which would you get

0.12 which is what she runs per minute

and then multiply that by 20

Answer 28

thank you!

Answer 29

No problemo! It's definitely 2.4 I checked myself :)

Answer 30

Your'e Welcome :)

Answer 31

Nice explanations, guys :D

Answer 32

Thanks @k_lynn