Wasserman (1989) studied a process for the manufacturing of steel bolts. Historically, these bolts have a mean thickness of 10.0 mm and a standard deviation of 1.6 mm. In a quality check, the engineer has a sample of 5 randomly selected and measured.
Assuming a near-normal distribution, what are the mean and standard deviation of the sample mean of these quality checks?

The mean of of the sample mean of these quality checks is 10 and the standard deviation is 0.7155.

Step-by-step explanation:

To solve this question, we use the central limit theorem.

The Central Limit Theorem estabilishes that, for a random variable X, with mean and standard deviation , the sample means with size n can be approximated to a normal distribution with mean and standard deviation

In this problem, we have that:

The mean of of the sample mean of these quality checks is 10 and the standard deviation is 0.7155.

25/4

step-by-step explanation:

call segment cd's length x. because dc and ab are parallel, angle acd and cab, so triangles adc and abc are similar and we can set up the equation x / ac = ac / ab, or x / 5 = 5 / 4 and x = 25/4.

13.33%

say 50 oranges, then 100 apples

80 are red, 20 are yellow

total fruit = 150

20chances out of 150 for yellow

20/150 = 13.33%