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

Automated notice from GMAT Club BumpBot:

A member just gave Kudos to this thread, showing it’s still useful. I’ve bumped it to the top so more people can benefit. Feel free to add your own questions or solutions.

This post was generated automatically.

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

Prep Toolkit

Top 5 GMAT Debrief Videos

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

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards

GMAT Problem Solving (PS) Questions

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)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards