A vending machine is designed to dispense 8 ouces of coffee into a cup. After a test that recorded the number of ounces in a cup of coffee in each of 1,000 cups dispensed by the vending machine, the 12 listed amounts in ounces, (see below) were selected from the data. If the 1,000 recorded amounts have a mean of 8.1 and a standard deviation of .3 ounce, how many of the 12 listed amounts are within 1.5 standard deviations of the mean?

7.51 8.22 7.86 8.3

8.09 7.83 7.96 8.36

7.73 8.25 8.01 8.53

A) 4

B) 6

C) 9

D) 10

E) 11

Argh - I can't figure out what I am doing wrong...Shouldn't the standard deviation yied a range of 7.8 - 8.4 hence 2 amounts are outside the standard deviation?? Please help

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