Question

Two dice are thrown simultaneously. What is the probability that the sum of the numbers appearing on the dice is
(i) 7? (ii) NOT a prime number? (iii) 1?

Answer 1

Answer:

(i) Sum of the number appearing on the dice is 7. (iii) Sum of the number appearing on the dice is 1. It is not possible, so its probability is zero

Answer 2

Answer:

According to the question,

Two dice are thrown simultaneously.

So, that number of possible outcomes =36

(i) Sum of the numbers appearing on the dice is 7.

So, the possible outcomes =(1,6),(2,5),(3,4),(4,3),(5,2),(6,1).

Hence, number of possible outcomes =6

∴ the probability that the sum of the numbers appearing on the dice is 7=  

36

6

​

=  

6

1

​

 

(ii) Sum of the numbers appearing on the dice is a prime number i.e. 2,3,5,7 and 11  

So, the possible ways are (1,1),(1,2),(2,1),(1,4),(2,3),(3,2),(4,1),(1,6),(2,5),(3,4),(4,3),(5,2),(6,1),(5,6) and (6,5)  

Number of possible ways =15  

∴ Required probability =  

36

15

​

=  

12

5

​

 

(iii) It is not possible, so its probability is zero

Step-by-step explanation: