Practicing Success

Target Exam

CUET

Subject

-- Mathematics - Section B1

Chapter

Probability

Question:

Two dice are thrown. Find the probability that the numbers appeared to have a sum of 8 if it is known that the second dice always exhibits 5.

Options:

2/3

4/5

5/6

1/6

Correct Answer:

1/6

Explanation:

A: Sum of the numbers is 8, i.e. {(2,6), (3,5), (4,4), (5,3), (6,2)} B: the second die always exhibits 5, i.e. {(1,5), (2,5), (3,5), (4,5), (5,5), (6,5)} A ∩ B= {(3,5)}

n(A ∩ B) = 1 

n(A) = 6 

$ P = \frac{1}{6} $