In a survey of 248 people, 156 are married, 70 are self-employed and 2

Question

In a survey of 248 people, 156 are married, 70 are self-employed and 25% of those who are married are self-employed. If a person is to be randomly selected from those surveyed, what is the probability that the person selected will be self-employed but not married?

A. 1/8
B. 4/31
C. 117/248
D. 1/4
E. 31/117

A. 1/8
B. 4/31
C. 117/248
D. 1/4
E. 31/117

whiplash2411 · Answer

I am not sure if my method is correct, but here's how I think you should approach this problem:

Total number of people = 248
Number of married people = 156
Number of self employed people = 70
Number of people who are married AND self employed = 25% of 156 = 39
Number of people who are self employed but not married = People self employed - People self employed/married

Thus, number of people who are self employed but not married = 70-39 = 31

Thus probability = 31/248 = 1/8

Does this match the correct answer specified?

Also, I've attached a diagrammatic view of how this might work.

@Others: Please let me know if my approach is right!

beraterschwein · Answer

I would put the figures into a table:
[tried to post link to my table - but due to the fact that i dont have enough posts/not long enough member of this forum can't post the link - pm me if you need it.

(Table columns: married, not-married, total
table rows: self-employed, not self-employed & total)

Than you can start to plug in the given values (Total surveyed: 248, total married: 156, total self-employed:70)

Now calculate 25% of 156 (share of self-employed & married)

And you end up with 39. It's quite easy to define all other values - but not needed for the anwer:

39/248=1/8

gsaxena26 · Answer

Many thanks. You have got it right.

generis · Answer

tableprob.png A double matrix works well here. The calculations are simple and few, but the categories are easier to see in a matrix. Total: 248 people Married: 156 Self-employed: 70 1) 25 percent of those who are married are self-employed: \frac{1}{4} * 156 = 39 2) Self-employed but not married: (70 - 39) = 31 3) Probability that a randomly selected person from all 248 will be self-employed but not married ( 31 ): \frac{31}{248} = \frac{1}{8} Answer A

testcracker · Answer

hi both self employed and married = 156 * (25/100) = 39 only self employed = 70 - 39 = 31 probability: only self employed / total = 31 / 248 = 1/8 thanks cheers through the kudos button if this helps

DanTheGMATMan · Answer

Straightforward overlapping sets problem:

https://www.youtube.com/watch?v=dd_Yr2VuNqg

bumpbot · Answer

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In a survey of 248 people, 156 are married, 70 are self-employed and 2

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In a survey of 248 people, 156 are married, 70 are self-employed and 2

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

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