Question 996518: 1. In a swimming race, a father gives his 4-year old son a 10-second head-start. The pool is 25-meters long. The child swims at 0.80 m/sec while the father swims at 1.20 m/sec.
a) How far is the child ahead of the father when the father gets to start swimming? [8 m]
b) At what time does the father come up alongside his son? [20 s later]
c) Who wins the race?
Answer by ankor@dixie-net.com(22740)   (Show Source):
You can put this solution on YOUR website! 1. In a swimming race, a father gives his 4-year old son a 10-second head-start.
The pool is 25-meters long.
The child swims at 0.80 m/sec while the father swims at 1.20 m/sec.
:
a) How far is the child ahead of the father when the father gets to start swimming? [8 m], this is how far he swims in 10 sec
:
b) At what time does the father come up alongside his son? [20 s later]
1.2t = .8(t+10)
1.2t = .8t + 8
1.2t - .8t = 8
.4t = 8
t = 8/.4
t = 20 sec
:
c) Who wins the race?
Find how far they are after 20 sec, 20*1.2 = 24 meters, therefore
Dad wins the race, but close, only by about .4 seconds
:
Son does the last meter in 1/.8 = 1.25 sec
Dad does the last meter in 1/1.2 = .833 sec
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