Find the least number which when divided by 16, 18, 20 and 25 leaves 4 as remainder in each case, but when divided by 7 leaves no remainder.

Explanation

First we have to find the LCM of `16,18,20 and 25`.

`16 = 2^4`

`18 = 2*3^2`

`20= 2^2*5`

`25 = 5^2`

so, LCM of these numbers will be `=2^4*3^2*5^2 = 3600`

Let the required number is `x`.

Then, `x = n**3600+4`

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