Jill walked 1.5 miles at 3 miles per hour. she then ran 4 miles at 6 miles per hour. which of the following rates is the closest to jill’s average rate over the total 5.5 miles? a. 3.5 miles per hour b. 3.8 miles per hour c. 4.2 miles per hour d. 4.7 miles per hour e. 5.3 miles per hour

Step-by-step explanation:

Given:

Jill walked 1.5 at the speed =3 miles per hour.

Jill ran 4 miles at the speed =6 miles per hour.

To find:

Average rate over the total 5.5 miles.

Formula used : speed = distance ÷ time

Solution:

Jill walked 3 miles = 1 hour.

Jill walked 1 miles = hour.

Jill walked 1.5 miles =1.5× .

Total  time for 1.5 miles  =0.5 hour.

Jill run 6 miles = 1 hour.

Jill run 1 miles = hour.

Jill walked 4 miles =4× .

Total  time for 4 miles  =0.67 hour

total time for 5.5 miles= 0.5+0.67= 1.17 hour

         Speed =distance÷time

         Speed= 5.5 miles÷ 1.17 hour

         Speed= 4.7 miles per hour

Therefore, the closest average rate over the total 5.5 miles is 4.7 miles per hour.