Coffee Vending machine - From GMAT Prep

[sanjeethbm]

7.51 8.22 7.86 8.36
8.09 7.83 8.30 8.01
7.73 8.25 7.96 8.53
A vending machine is designed to dispense 8 ounces of coffee into a cup. After a test that recorded the number of ounces of coffee in each of 1000 cups dispensed by the vending machine, the 12 listed amounts, in ounces, were selected from the data. If the 1000 recorded amounts have a mean score of 8.1 ounces and a standard deviation of 0.3 ounce, how many of the 12 listed amounts are within 1.5 standard deviations of the mean.

Four Six Nine Ten Eleven

How do I approach this problem?

- Sanjeeth

[Milanproda1]

There is a great explanation by Ron on Thursdays with Ron:

http://vimeo.com/15781353

Go to the 47 minute mark for the explanation

[sanjeethbm]

Thank you folks! Problem never looked simpler before.

- Sanjeeth

[RonPurewal]

thanks for the citation.