A school has 500 students, and B school has 800 students. Among these students there are 30 siblings pairs consisting of 1 A school student and 1 B school student. If 1 student is selected at random from both schools, what is the probability that a sibling pair is selected?
a) 3/40000, b) 3/20000, c) 3/4000, d)9/400, e)6/130
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Patrick_GMATFix
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There are 30 outcomes (selected pair) that would be considered a success.
The number of possible selections from School A is 500. The number of possible selections from School B is 800. Thus the total possible number of ways to pick someone in A and then someone in B is 500*800=40,000
Probability is success/all possibilities --> 30/40,000. The answer is C.
This question is written to match the OG11 #217 on page 182. Have a look at its solution to see whether you understand the Q.
The number of possible selections from School A is 500. The number of possible selections from School B is 800. Thus the total possible number of ways to pick someone in A and then someone in B is 500*800=40,000
Probability is success/all possibilities --> 30/40,000. The answer is C.
This question is written to match the OG11 #217 on page 182. Have a look at its solution to see whether you understand the Q.
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