Question

If the probability of A is 0.45 and the probability of the intersection of A and B is 0.15, then the probability that B will occur given that A has occurred is:

Group of answer choices

3.00

1.00

1/3

1/9

0.675

Members of a special marketing project team have decided to break the work up into smaller portions and divide it among sub-groups. There are 9 team members. How many different sub-groups are possible if each sub-group consists of 4 members and order doesn't matter?

Group of answer choices

362880

3024

126

42

24

The probability of drawing a seven, from a standard deck of 52 cards is 1/4.

Group of answer choices

True

False

Answer 1

Solution:

Question 1)

Given: P(A) = 0.45 and P(A and B) = 0.15

Find:

P( B|A) =..............?

P(B|A) = P( A and B) / P(A)

P(B|A) = 0.15 / 0.45

P(B|A) = 1 / 3

Question 2)
Given: There are 9 team members and we have to find number of different sub-groups are possible if each sub-group consists of 4 members and order doesn't matter.

If order doesn't matter, we use combination formula:

Question 3)

Given: The probability of drawing a seven, from a standard deck of 52 cards is 1/4.

Since in a deck of 52 cards, we have four cards of number "7", thus

P( drawing a seven) = 4 / 52

P( drawing a seven) = 1 / 13 which is not 1/4

thus given statement is False.