Answer:
Explanation:
Given
Distance to grandmother's house=100 mi
it is given that during return trip Julie spend equal time driving with speed 30 mph and 70 mph
Let Julie travel x mi with 30 mph and 100-x with 70 mph
[tex]\frac{x}{30}=\frac{100-x}{70}[/tex]
x=30 mi
Therefore
Julie's Average speed on the way to Grandmother's house[tex]=\frac{100}{\frac{50}{30}+\frac{50}{70}}[/tex]
=42 mph
On return trip
[tex]=\frac{100}{2\frac{30}{30}}=50 mph[/tex]
