Question

Maria drives at a rate of 60 miles per hour. It takes her 3 hours to get to her aunt’s house. How long will it take if she drives at a rate of 50 miles per hour?

Answer 1

3hrs annd 30 min

Explanation:

Let the distance to Maria's grandmother's house be 'x' miles.

She drove to her grandmother's place at an average speed of 60miles/hr.

This means she covered 60 miles in 60 minutes.

So time she took in covering 'x' miles is (x/60)60 = x minutes

On her way home she spanned 45 miles in 60 minutes.

So time she took in covering 'x' miles is (x/45)60 = (4x)/3 minutes

So total time taken was x + (4x)/3 minutes

But total time taken was = 3 hours 30 minutes = 210 minutes

So x + (4x)/3 = 210

or (3x + 4x)/3 = 210

or 7x = 210 * 3

or x = 630/7 = 90

Therefore the distance to her grandmother's place is 90 miles.

check: Time taken in going = x minutes = 90 minutes

Time taken in coming back = (4x)/3 = 120 minutes

Total time = 90 + 120 = 210 minutes = 3 hrs 30 minute

Answer 2

3.6hours

Explanation:

Since speed=distance/time

But according to the question,the distance she travelled is not stated in the question

So we will have to determine that

Speed=distance/time

Distance=speed×time

Distance=60×3

=180miles

So to determine the time when she travels at 50miles per hour

It will be time =distance/speed

Time=180/50

=3.6hours

Therefore the time to travel at 50miles per hour is 3.6hours