JEE Main 2021 (Online) 17th March Morning ShiftQuestion 1
Two dices are rolled. If both dices have six faces numbered $1,2,3,5,7$ and $11$, then the probability that the sum of the numbers on the top faces is less than or equal to $8$ is :
Probability
Solution
36 equally likely pairs. Count sum $\le 8$: for first die $1$: second $\in\{1,2,3,5,7\}$: 5; $2$: $\{1,2,3,5\}$: 4; $3$: $\{1,2,3,5\}$: 4; $5$: $\{1,2,3\}$: 3; $7$: $\{1\}$: 1; $11$: 0. Total $17$. $P=\frac{17}{36}$. Option (C).