Question

Jack spends 1 4/5 as long on his homework as Jill. Last week Jill spent 9 3/4 hours doing homework. How long did Jack spend doing homework?

Answer 1

About `17.6` hours.

Explanation:

If we let `a` = the number of hours Jack spent on his homework and `b` = the number of hours that Jill spent on her homework, we can set up an equation using the given information. Since Jack spent `1 4/5` times as long as Jill, this is the equation:

`a = 1 4/5 * b`

To make this a little easier on the eyes, you can convert the mixed number into a fraction.

`a = 9/5 * b`

Now, since we know that Jill spent `9 3/4` hours on her homework, simply plug that in as `b`.

`a = 9/5 * 9 3/4`

Now just simplify, to find that `a = 17.55`, or about `17.6` hours doing his homework.