# Probability Quiz Set 015

### Question 1

9 cones are lying inverted on a table. 2 of them contain balls, but 7 of them are empty. What is the probability of getting a ball if one of the cones is opened randomly?

A

\${2/9}\$.

B

\$3/9\$.

C

\$4/9\$.

D

\$7/9\$.

Soln.
Ans: a

Chances favoring a ball are 2, whereas the total chances are 9. The probability is 2/9 = \${2/9}\$.

### Question 2

49 defective pens are accidentally mixed with 84 good ones. It is not possible to just look at a pen and tell whether it is defective or not. One pen is taken out at random. What is the probability that it is a defective pen?

A

\${7/19}\$.

B

\$51/133\$.

C

\$8/133\$.

D

\$12/133\$.

Soln.
Ans: a

Out of the total number of pens = 133, the chances favoring defective pen are 49. So the probability is 49/133 = \${7/19}\$.

### Question 3

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.

### Question 4

From a deck of 52 cards 1 card is drawn at random. What is the probability that it will be a red "8"?

A

\${1/26}\$.

B

\$6/8\$.

C

\$2/26\$.

D

\$6/26\$.

Soln.
Ans: a

Number of ways of drawing 1 card = 52. There are two red "8" in the whole pack. So favorable chances are 2. Probability = 2/52 = 1/26.

### Question 5

A piggy bank contains 88 nos. of 50-paise coins, 37 nos. of 1-rupee coins and 34 nos. of 2-rupee coins. The piggy bank is turned upside down, and one coin falls down. What is the probability that it is a 50-paise coin?

A

\${88/159}\$.

B

\$34/159\$.

C

\$89/159\$.

D

\$93/159\$.

Soln.
Ans: a

Out of the total number of coins = 159, the chances favoring 50-paise coin are 88. So the probability is 88/159 = \${88/159}\$.