At a computer manufacturing company, the actual size of a particular type of computer chips is normally distributed with a mean of 1 centimeter and a standard deviation of 0.1 centimeter. A random sample of 12 computer chips is taken. What is the probability that the sample mean will be between 0.99 and 1.01 centimeters

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Answer:

So, the probability is P=0.27.

Step-by-step explanation:

We know that the mean of computer chips is 1 centimeter and a standard deviation of 0.1 centimeter. A random sample of 12 computer chips is taken.

We get:

[tex]n=12\\\\\mu=1\\\\\sigma=0.1\\[/tex]

We calculate:

[tex]z=\frac{(0.99-1)\cdot \sqrt{12}}{0.1}=-0.35\\\\z=\frac{(1.01-1)\cdot \sqrt{12}}{0.1}=0.35[/tex]

We use a table  for standard normal distribution, and we calculate the probability:

[tex]P(0.99<x<1.01)=P(-0.35<z<0.35)\\\\P(0.99<x<1.01)=P(z=0.35)-P(z=-0.35)\\\\P(0.99<x<1.01)=0.63-0.36\\\\P(0.99<x<1.01)=0.27\\[/tex]

So, the probability is P=0.27.

The probability that the sample mean will be between 0.99 and 1.01 centimeters is 26.62%

What is z score?

Z score is used to determine by how many standard deviations the raw score is above or below the mean. It is given by:

z = (raw score - mean) / (standard deviation÷√sample size)

Given;  mean of 1 cm, standard deviation of 0.1 cm, sample = 12

a) For 0.99:

z = (0.99 - 1)/(0.1 ÷ √12) = -0.34

For 1.01:

z = (1.01 - 1)/(0.1 ÷ √12) = 0.34

P(0.34 < z < -0.34) = P(z < 0.34) - P(z < -0.34) = 0.6331 - 0.3669 = 0.2662

The probability that the sample mean will be between 0.99 and 1.01 centimeters is 26.62%

Find out more on z score at: https://brainly.com/question/25638875