## PLEASE HELP 4. The table shows the probabilities of a response chocolate or vanilla when asking a child or adult. Use the formula for

PLEASE HELP

4. The table shows the probabilities of a response chocolate or vanilla when asking a child or adult. Use the formula for conditional probability to determine independence.

Chocolate | Vanilla | Total

Adults 0.21 0.39 0.60

Children 0.14 0.26 0.40

Total 0.35 0.65 1.00

a. Are the events “Chocolate” and “Adults” independent? Why or why not?

b. Are the events “Children” and “Chocolate” independent? Why or why not?

c. Are the events “Vanilla” and “Children” independent? Why or why not?

## Answers ( )

Answer:a) Yes the events Chocolate and Adults are independent

b) Yes the events Children and Chocolate are independent

c) Yes the events Vanilla and Children are independent

Step-by-step explanation:* Lets study the meaning independent and dependent probability

– Two events are independent if the result of the second event is not

affected by the result of the first event

– If A and B are independent events, the probability of both events

is the product of the probabilities of the both events

– P (A and B) = P(A) · P(B)

* Lets solve the question

# From the table:

– The probability of chocolate is 0.35

– The probability of vanilla is 0.65

– The probability of adults is 0.60

– The probability of children is 0.40

– The probability of chocolate and adults is 0.21

– The probability of chocolate and children is 0.14

– The probability of vanilla and adult is 0.39

– The probability of vanilla and children is 0.26

a.

∵ P(chocolate) = 0.35

∵ P(Adults) = 0.60

∵ Two events are independent if P (A and B) = P(A) · P(B)

∵ P(chocolate) · P(adults) = (0.35)(0.60) = 0.21

∵ P(chocolate and adults) = 0.21

∴ P(chocolate and adults) = P(chocolate) · P(adults)

∴ The events chocolate and adults are independent

b.

∵ P(chocolate) = 0.35

∵ P(children) = 0.40

∵ Two events are independent if P (A and B) = P(A) · P(B)

∵ P(chocolate) · P(children) = (0.35)(0.40) = 0.14

∵ P(children and chocolate) = 0.14

∴ P(chocolate and children) = P(chocolate) · P(children)

∴ The events chocolate and children are independent

c.

∵ P(vanilla) = 0.65

∵ P(children) = 0.40

∵ Two events are independent if P (A and B) = P(A) · P(B)

∵ P(vanilla) · P(children) = (0.65)(0.40) = 0.26

∵ P(vanilla and children) = 0.26

∴ P(vanilla and children) = P(vanilla) · P(children)

∴ The events vanilla and children are independent