Answer:
D. 4.7 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 =[tex]\frac{1}{3}[/tex] hour.
Jill walked 1.5 miles =1.5×[tex]\frac{1}{3}[/tex] .
Total time for 1.5 miles =0.5 hour.
Jill run 6 miles = 1 hour.
Jill run 1 miles =[tex]\frac{1}{6}[/tex] hour.
Jill walked 4 miles =4×[tex]\frac{1}{6}[/tex] .
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.
