Question

Julie drives 100 mi to Grandmother's house. On the way to Grandmother's, Julie drives half the distance at 44.0mph and half the distance at 65.0 . On her return trip, she drives half the time at 44.0mph and half the time at 65.0mph .

1)What is Julie's average speed on the way to Grandmother's house?

2)What is her average speed on the return trip?



*Express your answer with the appropriate units.

Answer 1

52.47706 mph

54.5 mph

Step-by-step explanation:

The average speed is given by

`V_(av)=(Distance)/(Time)`

`V_(av)=(100)/((50)/(44)+(50)/(65))\\\Rightarrow V_(av)=52.47706\ mph`

Julie's average speed on the way to Grandmother's house is 52.47706 mph

`V_(av)=(44+65)/(2)\\\Rightarrow V_(av)=54.5\ mph`

Average speed on the return trip is 54.5 mph