Question

After raining for 3/4 of an hour, a rain gauge is of 2/5 the way full. If it continues to rain at the same rate for 15 more minutes, what fraction of the rain gauge will be filled?

Answer 1

8/15

Explanation:

You want the fraction of a rain gauge filled after 15 more minutes when the rain rate is 2/5 of the gauge in 3/4 of an hour.

Proportion

15 minutes is 1/4 hour, so 15 more minutes brings the total time to 1 hour. The fraction (x) of the gauge that is filled will be ...

x/1 = (2/5)/(3/4)

x = (2/5)(4/3) = 8/15

After a total of 1 hour, the rain gauge will be 8/15 of the way full.