Proability

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Proability

by melcra » Fri Dec 19, 2008 10:28 am
Among a group of 2,500 people, 35 percent invest in municipal bonds, 18 percent invest in oil stocks, and 7 percent invest in both municipal bonds and oil stocks. If 1 person is to be randomly selected from the 2,500 people, what is the probability that the person selected will be one whio invests in municipal bonds but NOT in oil stocks?


(A) 9/50
(B) 7/25
(C) 7/20
(D) 21/50
(E) 27/50
Source: — Problem Solving |

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by parallel_chase » Fri Dec 19, 2008 10:50 am
MB = 32*25 = 875
OS = 25*18 = 450
both = 7*25 = 175

total = group 1 + group 2 - both + neither

only MB = MB - both = 875 -175 = 700

probability = 700/2500 = 7/25

Hope this helps.
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by melcra » Fri Dec 19, 2008 11:34 am
Thanks it does help. :D