Question

Last night, Roberto spent 90 minutes doing homework, two-thirds of an hour reading, and 540 seconds making his lunch for the next day. How many more minutes did Roberto spend doing homework than he did reading and making his lunch?

Answer 1

The answer is 41 minutes.

explaination:

540 secs = 9 minutes

2/3 of 60 mins= 40 mins

(to find a fraction of a number you divide it by the denominator and times it after by the numerator)

9+40= 49

homework: 90 mins

reading and making lunch: 49 minutes

we want the difference so:

90-49= 41

Roberto spent 41 more minutes doing his homework than reading and making lunch.