MHT CET202120 Sep 2021Morning ShiftMathematicsProbabilityActual
Two dice are rolled simultaneously. The probability that the sum of the two numbers on the dice is a prime number, is
Options
- A5 11
- B5 12
- C7 12
- D7 11
Correct answer
B. 5 12
Step-by-step solution
The sum of numbers on the two dice can be (2,3, ., 12) and prime numbers in this list are 2, 3, 5, 7, 11 . 2 (1,1) and 3 (1,2),(2,1) and 5 (1,4),(2,3),(3,2),(4,1) , 7 (1,6),(2,5),(3,4),(4,3),(5,2),(6,1) and 11 (5,6),(6,5) Thus n ( s )=6 6=36 and n ( E )=15 Hence required probability = 15 36 = 5 12