Marsha spends 150 minutes a night doing homework. Math homework takes ⅙ of that time.
Science homework takes 20% of that time.
Language Arts homework uses ⅓ of that time.

What percent of the time is left for Marsha’s social studies homework?

70%

Step-by-step explanation:

Maths homework takes 1/6×150mins

=150/6=25 mins

science homework takes 20/100×150

=3000/100

=30mins

Language Arts homework uses 1/3×150

=150/3

=50 mins

percent of time left for Marsha's social studies homework=total time used / original time

=(25+30+50)mins

=105mins/150mins×100%

=0.7×100

=70%

-250

Step-by-step explanation:

We could solve the problem above using integers. Integers are the set of whole numbers and their opposites. The number line is used to represent integers. So, when it is a 'decrease' it is negative.