Question

The table below gives the possible results if two die are rolled. 

If a blue and a red dice are rolled, what is the probability of rolling a "3" on the blue and a "2" on the red? 

A. 6/36  B. 2/36  C. 12/36  D. 1/36

Answer 1

Both the Red and Blue dies are rolled together.

Now we have to calculate probability that die blue gets number 3 and die red gets number 2.

Now,

Let event A : outcome of rolling of red die.

Event B: outcome of rolling of blue die.

Hence we have to calculate probability of getting A3 and B2 i.e P(A3 intersection B2) = P(A3)*P(B2) ; since event A and B are independent of each other.

Now P(A3) = 1/6 ; getting 3 in event A out of 6 possible way

P(B2)= 1/6 ; getting 2 in event B out of 6 possible way.

Hence P(A3 intersection B2) = 1/6 * 1/6 = 1/36.

Another possible way can be found by using definatiod of probability i.e favourable number of outcome upon total number of outcome.

Here favourable outcome is 1 i.e row 3 and column 2.

Total number of outcome = 36.

Hence probability = 1/36.