Question 1113991: A snail begins to climb a wall. Every hour it manages to climb up 30cm but it gets tired and slides back down 10cm. How long will it take for the snail to climb up the wall if the wall is 2.98m high
Answer by greenestamps(13195)   (Show Source):
You can put this solution on YOUR website!
The height of the wall is 2.98m = 298cm.
The snail will reach the top of the wall in the first hour that his starting point is within 30cm of the top of the wall -- that is, in the first hour in which his starting point is above 268cm.
He gains 20cm each hour; to reach 268cm or higher at 20cm/hr, he has to climb for 14 hours.
After 14 hours, he is at 280cm; he has 18cm to go to reach the top of the wall. At 30cm per hour, it will take him another 18/30 = 3/5 of an hour to go those 18cm.
So he will reach the top of the wall after 14 3/5 hours.
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