# Probability Quiz Set 004

### Question 1

A box contains 4 sky blue, 2 dark green and 8 khaki balls. What is the probability of drawing a ball that is neither dark green nor sky blue?

A

\${4/7}\$.

B

\$9/14\$.

C

\$5/91\$.

D

\$9/91\$.

Soln.
Ans: a

Total number of marbles is 14. We have to basically find the probability of picking a khaki ball, for which 8 chances are favorable. So probability = 8/14 = \${4/7}\$.

### Question 2

A bag contains 2 Red, 4 Blue and 8 Green marbles. What is the probability of drawing a Red marble if 2 marbles are drawn out randomly?

A

\${25/91}\$.

B

\$8/14\$.

C

\$26/91\$.

D

\$30/91\$.

Soln.
Ans: a

Total number of marbles is 14. Combinations of 2 marbles that are possible = 14C2 = \${14 × 13}/2\$ = 91. If one of the two balls is red, then red + red is one possibility, and 2 × (4 + 8) are the other possibilities. So total favorable outcomes = 1 + 2 × 12 = 25, and the probability is 25/91 = \${25/91}\$.

### Question 3

A box contains 4 maroon, 7 sky blue and 3 dark green balls. What is the probability of drawing a ball that is neither sky blue nor maroon?

A

\${3/14}\$.

B

\$4/14\$.

C

\$4/91\$.

D

\$8/91\$.

Soln.
Ans: a

Total number of marbles is 14. We have to basically find the probability of picking a dark green ball, for which 3 chances are favorable. So probability = 3/14 = \${3/14}\$.

### Question 4

A box contains 8 maroon, 5 navy and 3 pink marbles. What is the probability of drawing a marble that is not pink if 2 marbles are drawn out randomly?

A

\${13/20}\$.

B

\$3/16\$.

C

\$14/120\$.

D

\$18/120\$.

Soln.
Ans: a

Total number of marbles is 16. Combinations of 2 marbles that are possible = 16C2 = \${16 × 15}/2\$ = 120. Chances of drawing a non-pink ball are 13C2 = \$(13 × (13 - 1))/2\$ = 78. So probability = 78/120 = \${13/20}\$.

### Question 5

If P(E) = 0.59, then what is the probability of non-occurrence of E?

A

0.41.

B

0.59.

C

0.5.

D

0.25.

Soln.
Ans: a

P(E) + P(non-occurrence of E) is always = 1. So P(non-occurrence of E) = 1 - P(E) = 0.41. This Blog Post/Article "Probability Quiz Set 004" by Parveen (Hoven) is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
Updated on 2020-02-07. Published on: 2016-05-08