Question 1165415: A speedy tortoise can run at 0.15 m/s, and a
hare can run 16 times as fast. In a race, they
start at the same time, but the hare stops to
rest for 2.9 min, so the tortoise wins by a shell
(20 cm).
How long does the race take?
Answer in units of s
Answer by Boreal(15235)   (Show Source):
You can put this solution on YOUR website! tortoise goes 15 cm/sec; rabbit goes at 240 cm/sec or 2.4 m/sec.
so tortoise wins by 15/20 or 0.75 sec
the race takes s sec
tortoise went 15s cm
rabbit went 15s-20 cm
the rabbit's time running was 240 cm/sec and ran for (s-174) seconds, since 2.9 min is 174 sec
Then, 240 cm/sec *(s-174) sec=15s-20 cm
240s-41760=15s-20
225s=41740
s=185.51 seconds, or 3m5.51s
The tortoise went, in that time, 27.83 m or 2783 cm
The rabbit spent all but 11.51 sec resting, so the distance in 11.51 sec was 27.624 m, 0.2 m or 20 cm fewer.
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