700+ Veritas Quant

[chaitanya.mehrotra]

OA after some discussion

[edge]

You know, you can post the OA using spoiler tags. There's no need to 'post it after discussion'.

My answer is D.

We just need to know that the next three rolls have to be the same number, but different from the pair. The probability is P(a number different from the 'pair') x P(same as previous roll) x P(same as previous roll). This is 5/6 x 1/6 x 1/6 = 5/216.

[krishnasty]

IMO D

The first 2 dices have already been rolled out with a number.
the third dice should not have the previous number = (1-1/6) = 5/6
the next 2 rolls have to have the number which was rolled out at the third dice = (1/6) * (1/6)

total probablity = (5/6) * (1/6) * (1/6) = 5/216