Two dice are rolled simultaneously. Find the probability (a) of event sum of the digits on the upper faces is a prime number. (b) of event B that the sum digits on the upper faces is a multiple of 5.
Answers
Answer:
Formula:-
Probability=Favourable outcome/Total outcome
Two dices are rolled simultaneously:-
Outcomes possible:-
(1,1)P (1,2)P (1,3) (1,4)PF (1,5) (1,6)P
(2,1)P (2,2) (2,3)PF (2,4) (2,5)P (2,6)
(3,1) (3,2)PF (3,3) (3,4)P (3,5) (3,6)
(4,1)PF (4,2) (4,3)P (4,4) (4,5) (4,6)F
(5,1) (5,2)P (5,3) (5,4) (5,5) F (5,6)P
(6,1)P (6,2) (6,3) (6,4)F (6,5)P (6,6)
Total outcomes=36
A)
Favourable conditions=Sum of the above faces of the dice is a prime number
1. (1,1)
2. (1,2)
3. (2,1)
4. (2,3)
5. (3,2)
6. (1,4)
7. (4,1)
8. (2,5)
9. (5,2)
10. (3,4)
11. (4,3)
12.(1,6)
13. (6,1)
14. (5,6)
15. (6,5)
Probability=15/36
=5/12
B)
Sum of above faces is a multiple of 5
1.(1,4)
2.(4,1)
3.(2,3)
4.(3,2)
5.(5,5)
6.(6,4)
7. (4,6)
Probability=7/36