Question 194342
Angela drove 100 miles to Batonsville at an average speed of 50 miles per hour.
 She then increased her average speed by 20 percent and drove 30 miles to Catonsville. 
What was her average speed for the entire journey, in miles per hour?
:
Find the travel time of the 1st 100 mi
{{{100/50}}} = 2 hrs
;
Find the speed when increase by 20%
1.2*50 = 60 mph
:
Find the time to travel 30 mi at this speed
{{{3/60}}} = .5 hrs
:
Total distance: 100 + 30 = 130 mi
Total time: 2 + .5 = 2.5 hr
:
Find her av speed for the whole trip
{{{130/2.5}}} = 52 mph is her average speed for the whole trip