Question 72574This question is from textbook
: 1. You live in Pennsylvania and your grandparents live in Ohio. When you are in Pennsylvania, you drive an average rate of 55 mph. When you are in Ohio, you drive an average rate of 65 mph. The entire trip of 295 miles takes 5 hours. How long does it take to reach Pennsylvania-Ohio border? How long does it take to get from the border to your grandparents' house?
This question is from textbook
Answer by ankor@dixie-net.com(22740)   (Show Source):
You can put this solution on YOUR website! You live in Pennsylvania and your grandparents live in Ohio. When you are in Pennsylvania, you drive an average rate of 55 mph. When you are in Ohio, you drive an average rate of 65 mph. The entire trip of 295 miles takes 5 hours. How long does it take to reach Pennsylvania-Ohio border? How long does it take to get from the border to your grandparents' house?
:
Let t = time at 65 mph (Ohio part)
Let (5 - t) = time at 55 mph (Penn part)
:
Dist = time * speed:
:
65t + 55(5-t) = 295
65t + 275 - 55t = 295
65t - 55t = 295 - 275
10t = 20
t = 2 hrs at 65 mph, obviously 3 hrs at 55 mph then
:
Check using distance
2(65) + 3(55) =
130 + 165 = 295 mi total
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