# Probability Quiz Set 017

### Question 1

A piggy bank contains 73 nos. of 50-paise coins, 37 nos. of 1-rupee coins and 81 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

\${73/191}\$.

B

\$81/191\$.

C

\$74/191\$.

D

\$78/191\$.

Soln.
Ans: a

Out of the total number of coins = 191, the chances favoring 50-paise coin are 73. So the probability is 73/191 = \${73/191}\$.

### Question 2

A box contains 70 red balls and an unknown number of blue balls. If the probability of drawing a blue ball is 5 times the probability of drawing a red ball, then how many blue balls are there in the box?

A

350.

B

355.

C

345.

D

360.

Soln.
Ans: a

Let the number of blue balls be x. Chances of drawing a blue ball are \$x/{x + 70}\$ = 5 × \$70/{x + 70}\$, which gives x = 5 × 70 = 350.

### Question 3

What is the probability of getting a sum less than 12 from two throws of a dice?

A

1.

B

1/3.

C

2/3.

D

1/6.

Soln.
Ans: a

Total outcomes = 36. Favorable are 36 because sum will always be less than 12. So probability = 1.

### Question 4

From a deck of 52 cards two cards are drawn at random. What is the probability that both one is a clubs, and the other a diamonds?

A

\${13/102}\$.

B

\$9/14\$.

C

\$14/102\$.

D

\$18/102\$.

Soln.
Ans: a

Number of ways of drawing 2 cards out of 52 = 52C2 = \$(52 × 51)/2\$ = 1326. There are 13 clubs and 13 diamonds in the deck. So 2 such cards can be drawn in 13 × 13 = 169 ways. The probability = 169/1326 = 13/102.

### Question 5

If P(E) = 0.56, then what is the probability of non-occurrence of E?

A

0.44.

B

0.56.

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) = 0.44. 