(a)

Random sample for Column craze is .

Average price for Column craze is .

Assume that standard deviation is .

Find the probability that mean price is more than

Find .

Standard deviation of a sample mean is .

Substitute and in the formula.

.

Use the -value formula for a sample mean to find the -value for .

-value formula: .

Substitute , and .

.

Using -score calculator:

The area for is .

Area to the right side of is .

Probability that mean price is more than is .

(b)

Random sample for Space race is .

Average price for Space race is .

Assume that standard deviation is .

Standard deviation of a sample mean is .

Substitute and in the formula.

.

Find the probability that mean price is between and .

Find -value for .

-value formula: .

Substitute , and .

.

Using score calculator:

The area for is .

Find -value for .

-value formula: .

Substitute , and .

.

Using -score calculator:

The area for is .

Area between the -scores and is .

Probability that mean price between and is .

(a) Probability that mean price is more than is .

(b) Probability that mean price between and is .

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