Question

Evan listens to music on his MP3 while doing his chores. When he first turns on his MP3 player, it has 3/5 of its battery life left. When Evan finishes the chores, it has 35% of its battery life left. How much time does Evan spend doing chores if his MP3 player has 2 hours of battery life when fully charged?
I think the answer is 2hrs and 14 min.

Answer 1

3/5 = 60/100 = 60%
so started with 60% charge
60 - 35 = 25% used doing chores
so he used 25% of 2 hour charge = 1/2 hour
By the way:
If the battery only holds enough charge for 2 hours of use, how could he use 2 hours and 15 minutes?

Answer 2

Never mind, I know what I did wrong. Instead of subtracting the two I added. The answer is actually 30 minutes

Answer 3

Maya goes to the mall to buy some shoes. The shoes that she wants usually cost $42, but they were on sale for 40% less. There is a 5% sales tax, and Maya pays for the shoes with a $50 bill. how much change does Maya resive.