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A frog in the Well Quiz!!

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A frog in the Well Quiz!!

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A frog is at the bottom of the well which is 30 feet deep. Every night the frog jumps 3 feet up but during day time, it falls down 2 feet; how many days it will take for the frog to reach the top?


Picture source: Google
 
Prasad Sir,

It can not cling to the top on 27th day (starting from night to day ) since it will hop only up to 29'!

Night 1 ----
hop to 3' and slip to 1'

Night 2
----
hop to 4' and slip to 2'

Night 3
----
hop to 5' and slip to 3'

and so on....

Night 27
----
hop to 29' and slip to 27'

Night 28
----
hop to 30' and buzz off in the morning.
 
I have a doubt P J Sir! Usually people say that the frog jumps during the morning and slips during night (while sleeping?)!

But your frog is a special one which works at night!! :frog:

Ok! Now the formula for you.

If 'n' is the number of the night, the frog will reach n-1+3 and next morning slip to n-1+3-2 feet = n feet!!! So, 'n'th morning at n feet.

Hence, on 27th morning it will be at 27' and on the 28th night reach 28-1+3 = 30' which is the top and no need for -2! Clear??? :)
 
Raji Madam

It is a Special talent Frog !!!

Now you are confusing me with some mathematics !!!
 
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