Numbers + Probbability

ksvickram · Senior Consultant Joined: 02 Jan 2008 Posts: 29

If n is an integer from 1 to 96, what is the probability for n*(n+1)*(n+2) being divisible by 8?

Solve this if you can...

ksb · Posted: Wed Apr 23, 2008 5:25 pm Post subject:

Whenever 'n' is even, the product n * (n+2) will be divisible by 8 as one of the two numbers n or n + 2 will be divisible by 4 and the other by 2.

That gives 48 numbers in the set 1 to 96.

Plus when (n + 1) = 8, the number will be divisible by 8. there are 12 multiples of 8 in the set 1 to 96. So, there are 12 values that 'n' can take where n + 1 is divisible by 8. And in all these cases 'n' will be odd. So, there is no element common in this 12 and the earlier 48.

So, a total 60 values out of 96.