# Standard Deviation

A vending machine that dispenses coffee into cups must fill the cups with 7.8oz of liquid. Before selling the vending machine to a college or business, the company tests the machine to be sure it is dispensing an average amount of 7.8oz of coffee. A sample of 20 amounts is shown below. The amount of coffee dispensed is assumed to be normally distributed with a standard deviation of 0.05 oz.

Ounces dispensed

7.78 7.79

7.82 7.82

7.87 7.84

7.80 7.82

7.80 7.78

7.83 7.75

7.85 7.83

7.84 7.73

7.82 7.87

7.81 7.88

https://brainmass.com/statistics/hypothesis-testing/standard-deviation-8067

#### Solution Preview

sum (x) = summation of data = 156.33

<br><x> = average = sum(x)/n = 156.33/20 = ...

#### Solution Summary

A vending machine that dispenses coffee into cups must fill the cups with 7.8oz of liquid. Before selling the vending machine to a college or business, the company tests the machine to be sure it is dispensing an average amount of 7.8oz of coffee. A sample of 20 amounts is shown below. The amount of coffee dispensed is assumed to be normally distributed with a standard deviation of 0.05 oz.

Ounces dispensed

7.78 7.79

7.82 7.82

7.87 7.84

7.80 7.82

7.80 7.78

7.83 7.75

7.85 7.83

7.84 7.73

7.82 7.87

7.81 7.88