Median of their weights

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Median of their weights

by kulksnikhil » Mon Nov 27, 2006 3:47 am
Question is not gramatically correct... but it is understandable..

500 birds, 75% is lighter than 134g. 60% of the birds heavier than 100g is heavier than 134g. What is the median of their weights?

Can anybody help me solve this?

Answer could be 92

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Re: Median of their weights

by gmat_enthus » Mon Nov 27, 2006 7:12 am
kulksnikhil wrote:Question is not gramatically correct... but it is understandable..

500 birds, 75% is lighter than 134g. 60% of the birds heavier than 100g is heavier than 134g. What is the median of their weights?

Can anybody help me solve this?

Answer could be 92
Let there be three ranges:
w<100
100<w<134
134<w

Let the total greater than 100 be x

Given for greater than 100, 60% of them are greater than 134 =>
100<w<134 = 0.4x
w>134 = 0.6x

Let the total weights be T.
Given that 0.75% of T is less than 134 => 25% of T is > 134
=> 0.6x=0.25T => T=2.4x

In terms of x total weights = 2.4x. so the median will the weight at at 1.2x [approaximately]

In terms of x, the distribution is:
w<100 -> 1.4x
100<w<134 -> 0.4x
134<w -> 0.6x

So the median will lie in the range x<100
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by kulksnikhil » Sat Dec 02, 2006 5:48 am
that's a great explaination.. thx... there were no options given.. probably could haev selected one of the options.. if available