question from gmatperp -- vending machine

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Source: — Data Sufficiency |

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by abhinav85 » Sat Jun 20, 2009 9:51 am
OA is 11.

The question says that mean of the 12 amounts is 8.1 and
the standard deviation is 0.3.

So how many values comes under 1.5 SD from the mean.

The range will be 7.65 - 8.75.

So 11 values.
Last edited by abhinav85 on Sat Jun 20, 2009 10:01 am, edited 2 times in total.

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by hetavdave » Sat Jun 20, 2009 9:54 am
hmm... got that..1.5 x (0.3)

thnx a ton