Answer:
15 minutes.
Explanation:
One hour is equal to 60 minutes. Since you're asking for 1/4, or a quarter, of that amount of time, we should divide 60 by four.
Using a calculator, you'd get 15 asap. Without one, if you can divide 60 in half (that equals 30), then divide that half in half again (that equals 15), you'll have divided it into quarters and gotten your answer.