Question

how many miles can a motorist travel from 9.55am to 10.15am at a rate of 40 miles per hour?

Answer 1

Motorist travels from 9:55 am to 10:15 am.

Total time t = 20 min
So, t = (20/60) h = (1/3) h

Now, speed v = 40 mph
Let distance travelled be d

Now, speed = distance/time
So, d = v×t
So, d = (40)×(1/3) = 13.33 miles

Thus, the motorist can travel 13.33 miles in the given time.

Answer 2

In an hour a motorist travels 40 miles. Means he travels 20 miles in 30 minutes.
Thus he travels 10 miles in 15 minutes. 
  Hence, in 5 minutes he travels 3.33 miles.

Now from 09.55 am to 10.15 am he's traveled 20 minutes.
       20 minutes =  5 * 4 minutes.
                          = 3.33 * 4 miles
                          = 13.32 miles 

Thus the motorist has traveled 13.32 miles (approx.) at the speed of 40 miles per hour.


Thank You!