14
Q:

# A brother and a sister appear for an interview against two vacant posts in an office. The probability of the brother’s selection is 1/5 and that of the sister’s selection is 1/3. What is the probability that only one of them is selected?

 A) 1/5 B) 3/4 C) 2/5 D) 3/5

Explanation:

Probability that only one of them is selected = (prob. that brother is selected) × (prob. that sister is not selected) +  (Prob. that brother is not selected) × (Prob. that sister is selected)

$15*23+45*13$$25$

Q:

Find the range and mode of the data 17, 18, 28, 19, 16, 18, 17, 29, 18

 A) 12 and 18 B) 13 and 18 C) 12 and 17 D) 11 and 17

Answer & Explanation Answer: B) 13 and 18

Explanation:

5 281
Q:

Find the standard deviation of {11, 7, 10,13, 9}

 A) 1 B) 2 C) 4 D) 5

Explanation:

2 251
Q:

A table tennis player, lost 12 games out of 18 games played. Calculate the games won in terms of decimal.

 A) 0.667 B) 0.067 C) 0.50 D) 0.333

Explanation:

1 370
Q:

A sequence , has odd number of terms. Then the median is

 A) axn2+1 B) axn2-1 C) axn-1 D) axn2

Explanation:

3 2303
Q:

The mean of a distribution is 15 and the standard deviation is 5. What is the value of the coefficient variation?

 A) 16.66% B) 66.66% C) 33.33% D) 100%

Explanation:

5 612
Q:

If the standard deviation of a population is 3, what would be the population variance?

 A) 9 B) 6 C) 8 D) 15

Explanation:

3 2936
Q:

The variance of a set of data is 169. Then the standard deviation of the data is

 A) +-13 B) 13 C) 69 D) 84.5

Explanation:

3 2391
Q:

If the standard deviation of a population is 10, what would be the population variance?

 A) 100 B) 30 C) 5 D) 20

Explanation: