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probabilities JJ

by enriqueta26 » Mon Jul 19, 2010 10:34 am
Could someone help me with this one , please?

Joshua and Jose work at auto repair center with 04 other workers. For a survey on health care insurance, 2 of the 6 workers will be randomly chosen to be interviewed. What is the probability that Joshua and Jose will both be chosen
?
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[spoiler]A: 1/15[/spoiler]
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by kmittal82 » Mon Jul 19, 2010 11:06 am
Total number of ways to select 2 people out of 6 = 6C2 = 15

Only 1 group can have both Joshua and Jose in it, thus favourable conditions = 1

Thus probability = 1/15
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by Patrick_GMATFix » Mon Jul 19, 2010 11:17 am
Hi Enriqueta,

Please post the answer choices when you post your number.

This is a combination problem. There are 6 people from which 2 will be selected. This means that the total number of ways to pick people is a combination of 2 from 6: 6!/(2!4!) = 15.

Of these 15 possible group, only one group of 2 will include both Joshua and Jose. Therefore the probability that they are both picked is 1/15

The correct answer is A. A more detailed explanation as well as video solution can be viewed at GMATPrep Question 1208. To practice similar questions, set topic='combinatorics' and difficulty='600-700 & 700+' in the Drill Generator

Good luck,
-Patrick

This question is also discussed at https://www.beatthegmat.com/combinations ... 61419.html
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