Question 1143273: There is a frog stuck in a 19 meter well. How many days will it take the frog
to get out if every day he jumps ten feet up, but falls back 5 meters?
A)3
B)4
C)5
D)7
Answer by Edwin McCravy(20056)   (Show Source):
You can put this solution on YOUR website! There is a frog stuck in a 19 meter well. How many days will it take the frog
to get out if every day he jumps ten meters up, but falls back 5 meters?
He needs to be 19 meters from the bottom.
On his 1st jump, he jumps up 10 meters, from the bottom.
Now he is 10 meters from the bottom, and still has 9 meters to go.
But he falls back 5 meters.
So now he is 5 meters from the bottom, and still has 14 meters to go.
On his 2nd jump, he jumps up 10 meters from 5 meters above the bottom
Now he is 15 meters from the bottom, and still has 4 meters to go.
But he falls back 5 meters.
Now he is 10 meters from the bottom, and still has 9 meters to go.
So on his 3rd jump, he jumps up 10 meters from 10 meters above the bottom, he
is 1 foot above the top of the well, so he is out and will not fall back.
So he gets out on his third jump.
Answer: 3
Edwin
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