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Get rich A survey of 4826 randomly selected young adults (aged 19to25) asked, 鈥淲hat do you think are the chances you will have much more than a middle-class income at age 30?鈥 The two-way table summarizes the responses.

Choose a survey respondent at random. Define events G: a good chance, M: male, and N: almost no chance.

a. Find P(G|M). Interpret this value in context.

b. Given that the chosen survey respondent didn鈥檛 say 鈥渁lmost no chance,鈥 what鈥檚 the probability that this person is female? Write your answer as a probability statement using correct symbols for the events.

Short Answer

Expert verified

a. Required probability is P(GM)0.3083

b. Probability of female respondent didn't say "almost no chance" isPMcNc0.4903

Step by step solution

01

Given Information

It is given that:

02

Determining probability for male young adult having good chance of much more than middle class income at age 30

Using Conditional Probability: P(BA)=P(AB)P(A)=P(AandB)P(A)

G: Good Chance

M: Male

Information about 4826young adults is provided.

From table, 2459/4826young adults are males.

P(M)=Number of favourable outcomesNumberof possible outcomes=24594826

Also, 78/4826young adults have a good chance.

P(GandM)=Number of favourable outcomesNumberof possibleoutcomes=7584826

Using Conditional Probability

P(GM)=P(GandM)P(M)=758482622594826=75824590.3083=30.83%

Hence, 30.83%of young males are of the view that there is good chance for them to have much more than middle aged income at30and probability is0.3083

03

Determining probability of the female respondent didn't say "almost no chance".

As per complement rule,

PAc=P(notA)=1-P(A)

and conditional probability P(BA)=P(AB)P(A)=P(AandB)P(A)

N: Almost no chance

M: Male

From table, 194/4826young adults think that "Almost no chance".

4632young adults do not have such opinion.

PNc=Numberof favourable outcomesNumberof possibleoutcomes=46324826

From table, 96/4826female adults have opinion "Almost no Chance".

As total female young adults are 2367.

2271/4826female young adults dis not have above opinion.

PMcandNc=Numberof favourableoutcomesNumber of possible=22714826

Using Conditional Probability:

PMcNc=PMcandNcPNc=2271422646324826=22714632=75715440.4903=49.03%

Hence, probability for the female respondent didn't say "almost no chance" is0.4903

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