test23 3 13

dunkin77 · Posted: Mon Apr 23, 2007 11:13 am Post subject: test23 3 13

Hi,

The answer is D) but can anyone give me explanation?

Thanks!

rajeshvellanki · Posted: Mon Apr 23, 2007 11:43 am Post subject:

okay here you go:

The only number which satisfies the given condition is : 101

and a(n)=a(1)+(n-1)d

199=100+(n-1)d

==> n=100 terms

Probability of selecting 1 number out of 100 numbers is 1/100 hence D

R

Cybermusings · Posted: Wed Apr 25, 2007 6:06 am Post subject:

Since we have to pick a number between 100 and 199 both inclusive...it is imperative that the hundreds digit is always 1....for the hundreds and last digit always to be 1 more than the middle digit...the last digit has to be 1 and the middle digit 0

There is only 1 such number i.e. 101

So probability = 1/100