QUESTION 11

1. The mean sale price of a new one bedroom unit in Western Australia is $200,000. A sample of 100 new one bedroom units is selected. Assume that the population standard deviation is $25,000 and the sale price of one bedroom units is normally distributed. The standard error of the sample mean is(in dollars, zero decimal places).

The probability that the average sale price of this sample of one bedroom units will be greater than $195,000 is(4 decimal places).

1 points

QUESTION 12

The owner of a coffee shop has found that the average amount spent by a sample of 25 customers is $8.60 with a sample standard deviation of $1.4. What are the lower and upper bounds of a 90% confidence interval for the population mean amount spent (in dollars) by customers?

1. (6.32, 7.28)
2. (6.34, 7.26)
3. (8.12, 9.08)
4. (9.50, 9.70)