Question

Vera

using her phone is battery life is down to 2/5 and it drains another 1/9 every hour how many hours will the battery last

Answer 1

2/5 of 100 would be 40%
1/9 an hour would be 1/9 x 40 % = 4.44% every hour
Total hours left would be 40% / 4.44%= 9.0009 = 9 hours

Answer 2

18/5 hours

Explanation:

If Vera's phone has a battery life of 2/5 and it drains 1/9 every hour we can determine how much per hour her battery drains.

f the battery drains 1/9 per hour we know how much it drains per hour. To get the time is takes for 2/5 battery life to drain we can say 2/5 divided by 1/9.

`=(2/5)/(1/9)=(2/5)*(9/1)`

We have 5 and 1 at the bottom of the line and 9 and 2 at the top of the line. We can simplify:

`=18/5`

It takes 18/5 hours for Vera's battery to last