Question

Hector has 3/4 hour to spend his homework. He wants to spend 1/3 of this time on math homework, 10 minutes of his time on reading homework, and the remaining time on science homework. How much time, in minutes, does Hector have to spend on his science homework?

Answer 1

20 minutes

Explanation:

Remember that

`1\ h=60\ mi`

we know that

Hector has 3/4 hour to spend his homework

Convert to minutes

`(3)/(4)(60)=45\ min`

so

1) He wants to spend 1/3 of this time on math homework

To find out the time on math homework, multiply 45 minutes by 1/3

`45((1)/(3))=15\ min`

2) He wants to spend 10 minutes of his time on reading homework

3) He wants to spend the remaining time on science homework

The time spend on math homework plus the time spend reading homework, plus the time spend on his science homework must be equal to 45 minutes

Let

x ----> the time spend on his science homework

`15+10+x=45`

Solve for x

`25+x=45\\x=45-25\\x=20\ min`