A fast-food restaurant uses an automated filling machine to pour its soft drinks. The machine has different settings for small, medium, and large drink cups. According to the machine’s manufacturer, when the large setting is chosen, the amount of liquid dispensed by the machine follows a Normal distribution with mean 27ounces and standard deviation0.8ounces. When the medium setting is chosen, the amount of liquid dispensed follows a Normal distribution with mean 17ounces and standard deviation 0.5ounces. To test the manufacturer’s claim, the restaurant manager measures the amount of liquid in a random sample of 25cups filled with the medium setting and a separate random sample of 20cups filled with the large setting. Let x¯1-x¯2be the difference in the sample mean amount of liquid under the two settings (large – medium). Find the mean and standard deviation of the sampling distribution.

Short Answer

Expert verified

It is approximately normally distributed.

Step by step solution

01

Given information

Sample mean=27

Sample mean=17

Standard deviation=0.8

Standard deviation=0.5

02

Step : Explanation

Given is written as

x¯1=27

x¯2=17

σ1=0.8

σ2=0.5

It has been assumed that population distributions are normal. As a result, the sample distribution of x¯1-x¯2can be considered to be approximately regularly distributed.

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