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Expert replies
by rohanberi » Sun Aug 07, 2011 11:04 am
Hi,

Please help me find answer to the following question:-

1000 animals, mean height 60, standard deviation 10.
How many animals have height between 70 and 80.
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Source: — Problem Solving |

by gmatboost » Sun Aug 07, 2011 10:31 pm
This is not on the GMAT. Do not waste your time memorizing SD percentiles. Stop using whatever prep material is telling you to do that.

Better still, there is no answer to this question as stated, because it doesn't say there is a normal distribution.
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by rohanberi » Mon Aug 08, 2011 5:07 am
Thanks Greg.

It wasn't a question given in some study material.
I came across this question, but wasn't able to solve, so asked.
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