average!

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average!

by fruti_yum » Sun Aug 02, 2009 10:09 am
Was the average (arithmetic mean) weight of the package mailed at a certain post office yesterday greater than 600 grams?
(1) The total weight of the packages mailed at the post office yesterday was greater than 14,500 grams.
(2) Fewer than 25 packages were mailed at the post office yesterday.

OA is C

I didnt know how to approach such a question.. Can you pls help me??

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by shahdevine » Sun Aug 02, 2009 12:17 pm
statement 1)

14500 grams/# of packages

insufficient

statement 2)

X grams/(# of packages<25)

insufficient

Combined.

14,500 grams/(1<=packages<25)

You are seeing if after you divide 14,500 by 24 is the result greater than 600 grams on average. The answer is yes...and as check numbers less than 24, the average number of grams increases. So sufficient.