192
Q:

# A bag contains 4 white, 5 red and 6 blue balls. Three balls are drawn at random from the bag. The probability that all of them are red, is:

 A) 2/91 B) 1/22 C) 3/22 D) 2/77

Explanation:

Let S be the sample space.

Then, n(S) = number of ways of drawing 3 balls out of 15 = $15C3$  =$15*14*133*2*1$= 455.

Let E = event of getting all the 3 red balls.

n(E) = $5C3$ = $5*42*1$ = 10.

=> P(E) = n(E)/n(S) = 10/455 = 2/91.

Subject: Probability
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

Explanation:

Filed Under: Probability
Exam Prep: Bank Exams

15 1138
Q:

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

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

Explanation:

Filed Under: Probability
Exam Prep: Bank Exams

3 837
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:

Filed Under: Probability
Exam Prep: Bank Exams

3 806
Q:

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

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

Explanation:

Filed Under: Probability
Exam Prep: Bank Exams

3 6425
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:

Filed Under: Probability
Exam Prep: Bank Exams

5 891
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:

Filed Under: Probability
Exam Prep: Bank Exams

4 6546
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:

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Exam Prep: Bank Exams

3 5316
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:

Filed Under: Probability
Exam Prep: Bank Exams

6 865