# Kristen loves to bake cookies, but she has an old oven that has trouble maintaining a constant...

## Question:

Kristen loves to bake cookies, but she has an old oven that has trouble maintaining a constant temperature. If the acceptable temperature range for making the cookies is 350 plus or minus 5 degrees, what is the allowable standard deviation in the temperature of her oven in order to achieve a Six Sigma level of quality?

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A. What is the allowable temperature range to achieve 6 sigma level?

B. What is the allowable temperature range to achieve 3 sigma level?

## Process Capability Ratio:

The process capability ratio, also known as the process capability index, is a measure of statistics used to measure the capability of a process. This measurement is completed considering the specification limits of the process.

## Answer and Explanation:

a) The allowable temperature range to achieve 6 sigma is +/- .83 degrees. This is calculated by taking the 10 degree range (350 plus or minus 5 degrees) and dividing by 12: 10/12 = .8333333

b) The allowable temperature range to achieve 3 sigma is +/- 1.66667 degrees. This calculated by taking the 10 degree range and dividing by 6: 10 / 6 = 1.66666666667