The average weight of 15 items is 8 kg. The least average weight of 5 items of these 15 is 5 kg. If no item weighs less than 5 kg, what is the maximum number of items that can have the same weight?
(C) 2008 GMAT Club - m14#15
15 items cannot have the same weight. It would contradict the statement that the least average weight of 5 items is 5 kg. But 14 items can have the same weight of 5 kg. The 15th item will have to weigh 50 kg to make the average weight equal 8 kg.
The correct answer is E.
Hello, can somebody elaborate on this problem ?
Total weight of these 15 items is 15*8=120 kg.
Now, as average weight of 5 items out of 15 is 5 kg. and as no item weighs less than 5 kg, then each of these 5 lightest items weight exactly 5kg.
But there might be more than 5 items with weight of 5kg. Why not 14? 14*5=70 and in this case the the las item will be 50 kg to make the average wight of 8kg (70+50=120).
Hope it's clear.
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