Question

Benny's water bottle has 15 oz of water and he drinks 0.5 oz. per second. Juan water bottle has 10 oz. of water and he adds 0.25 oz. per second. After how many seconds will Benny's water bottle have no more than Juan's

Answer 1

Let s represent the number of seconds it will take for Benny's water bottle to have no more than Juan's.

We were told that Benny's water bottle has 15 oz of water and he drinks 0.5 oz. per second. It is reducing. This means that the amount that he would have after s seconds is

15 - 0.5s

Also, Juan water bottle has 10 oz. of water and he adds 0.25 oz. per second. It is increasing. This means that the amount that he would have after s seconds is

10 + 0.25s

If Benny's water bottle have no more than Juan's, it means that they are equal. Thus

15 - 0.5s = 10 + 0.25s

0.25s + 0.5s = 15s - 10s

0.75s = 5s

s = 5/0.75

s = 6.67

It will take 6.67 seconds