JEE MAIN - Mathematics (2021 - 17th March Morning Shift - No. 8)
Two dies 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 :
$${4 \over 9}$$
$${1 \over 2}$$
$${5 \over {12}}$$
$${17 \over {36}}$$
Explanation
n(S) = 36
possible ordered pair :
(1, 1), (1, 2), (1, 3), (1, 5), (1, 7),
(2, 1), (2, 2), (2, 3), (2, 5),
(3, 1), (3, 2), (3, 3), (3, 5),
(5, 1), (5, 2), (5, 3),
(7, 1)
Number of favourable outcomes = 17
Probability = $${{17} \over {36}}$$
possible ordered pair :
(1, 1), (1, 2), (1, 3), (1, 5), (1, 7),
(2, 1), (2, 2), (2, 3), (2, 5),
(3, 1), (3, 2), (3, 3), (3, 5),
(5, 1), (5, 2), (5, 3),
(7, 1)
Number of favourable outcomes = 17
Probability = $${{17} \over {36}}$$
Comments (0)
