Question 640754: One speed skater starts across a frozen lake at an average speed of 8 meters per second. Ten seconds later, a second speed skater starts from the same point and skates in the same direction at an average speed of 10 meters per second. How many seconds after the second skater starts will the second skater overtake the first skater?
Answer by ankor@dixie-net.com(22740)   (Show Source):
You can put this solution on YOUR website! One speed skater starts across a frozen lake at an average speed of
8 meters per second.
Ten seconds later, a second speed skater starts from the same point and
skates in the same direction at an average speed of 10 meters per second.
How many seconds after the second skater starts will the second skater
overtake the first skater?
:
Let t = time (in sec) of the second skater, when he overtakes the 1st one
then
(t+10) = time of the 1st skater
:
When one overtakes the other they will have traveled the same distance
Write a distance equation for each skater: dist = speed * time
:
10t = 8(t+10)
10t = 8t + 80
10t - 8t = 80
2t = 80
t = 40 seconds after the 2nd skater starts, he catches the 1st skater
:
:
Check this by finding the actual dist traveled by each skater
10*40 = 400 meters
8(40+10) = 400 meters also
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