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ps 500 test21 #16

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by dunkin77 » Sun Apr 08, 2007 12:30 pm
Hi,

The correct answer is E) but I need an explanation why.... please anyone help? thanks.

16. Of the science books in a certain supply room, 50 are on botany, 65 are on zoology, 90 are on physics. 50 are on geology, and 110 are on chemistry. If science books are removed randomly from the supply room, how many must be removed to ensure that 80 of the books removed are on the same science?
(A) 81
(B) 159
(C) 166
(D) 285
(E) 324
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Re: ps 500 test21 #16

by gabriel » Mon Apr 09, 2007 7:46 am
dunkin77 wrote:Hi,

The correct answer is E) but I need an explanation why.... please anyone help? thanks.

16. Of the science books in a certain supply room, 50 are on botany, 65 are on zoology, 90 are on physics. 50 are on geology, and 110 are on chemistry. If science books are removed randomly from the supply room, how many must be removed to ensure that 80 of the books removed are on the same science?
(A) 81
(B) 159
(C) 166
(D) 285
(E) 324

q has already been discussed ... read this https://www.beatthegmat.com/viewtopic.php?t=1695 ...
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