SOLUTION: one speed skater starts across a frozen lake at 8 meters per sec. 10 sec later a second skater starts from the same point in the same direction at 10 meter per sec. how many sec af

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Question 364294: one speed skater starts across a frozen lake at 8 meters per sec. 10 sec later a second skater starts from the same point in the same direction at 10 meter per sec. how many sec after the second skater starts will she catch the first skater.
i know the answer to the problem. it is 40 sec. i just don't know how to get it

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
one speed skater starts across a frozen lake at 8 meters per sec. 10 sec later a second skater starts from the same point in the same direction at 10 meter per sec. how many sec after the second skater starts will she catch the first skater.
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The easy way:
The 1st skater is 80 meters ahead (8 * 10)
The 2nd skater gains on him at 2 m/sec (10 - 8)
80/2 = 40 seconds
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The hard way:
When he catches the 1st skater, they will have gone the same distance.
10*t = 8*(t+10)
10t = 8t + 80
2t = 80
t = 40 seconds
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PS Einstein would use the 1st method.