Question

Two dice, one blue and one grey, are thrown at the same time. Write down all the possible outcomes. What is the probability that the sum of the two numbers appearing on the top of the dice is:

(i) 8? (ii) 13? (iii) less than or equal to 12?

Answer 1

When the blue die show '1', the grey die could show one of the number 1,2,3,4,5,6. The same is true when the blue die show '2', '3', '4', '5', '6'. The possible outcome of the experiment are listed in the table below; the first number in each ordered pair is the number appearing on the blue die and the second number is that on the gray die.

so, the number of possible outcomes =6x6=36

(i) The outcomes favorable to the event the sum of the two number is 8 denoted by E, are:

(ii) As you can see from the figure, there is no outcome favorable to the event F, the sum of two numbers is 13.

So,   P(F)=0/36=0

(iii) As you can see from figure, all the outcomes are favorable to the event G,'sum of two numbers ≤ 12'

So, P(G)=36/36=1.