SOLUTION: 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 w

Algebra ->  Average -> SOLUTION: 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 w      Log On


   



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 wverage speed for the entire journey, in miles per hour?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
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%2F50 = 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%2F60 = .5 hrs
:
Total distance: 100 + 30 = 130 mi
Total time: 2 + .5 = 2.5 hr
:
Find her av speed for the whole trip
130%2F2.5 = 52 mph is her average speed for the whole trip