Test Index

Probability

Question : 69 of 127

Marks: +1, -0

9 ?

Solution:

Concept:

Probability of an event = (number of favorable outcomes) / (total outcomes).

Explanation:

Total outcomes when rolling two unbiased dice =

6 \times 6 = 36

Outcomes for sum = 6:

(1,5), (2,4), (3,3), (4,2), (5,1)

→ 5 outcomes.

Outcomes for sum = 9:

(3,6), (4,5), (5,4), (6,3)

→ 4 outcomes.

Total outcomes with sum 6 or 9 =

5 + 4 = 9

Probability of sum 6 or 9 =

\frac{9}{36} = 0.25

Probability of neither 6 nor 9 =

1 - 0.25 = 0.75

Answer:

0.75

Go to Question:

Prev Question

Next Question