106
Q:

# In a class, there are 15 boys and 10 girls. Three students are selected at random. The probability that 1 girl and 2 boys are selected, is:

 A) 21/46 B) 1/5 C) 3/25 D) 1/50

Explanation:

Let , S -  sample space        E - event of selecting 1 girl and 2 boys.

Then, n(S) = Number ways of selecting 3 students out of 25

= $25C3$

= 2300.

n(E) = $10C1×15C2$ = 1050.

$\inline \fn_jvn \therefore$P(E) = n(E)/n(s) = 1050/2300 = 21/46

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 1125
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

3 807
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

3 788
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 6350
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

5 880
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 6484
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:

Filed Under: Probability
Exam Prep: Bank Exams

3 5263
Q:

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

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