We want to estimate the population mean within 5, with a 99% level of confidence. The population standard deviation is estimated to be 15. How large a sample is required?(Round the final answer to the nearest whole number.)

Sample size

The bank in Cobden, Ontario, has 650 chequing account customers. A recent sample of 50 of these customers showed 26 to have a Visa card with the bank.

Construct the 99% confidence interval for the proportion of chequing account customers who have a Visa card with the bank.(Round the final answers to 3 decimal places.)

The 99% Confidence interval for the proportion of chequing account customers is betweenand.

The mean of a normal probability distribution is 340; the standard deviation is 9.

a.About 68% of the observations lie between what two values?

Lower Value

Upper Value

b.About 95% of the observations lie between what two values?

Lower Value

Upper Value

c.Nearly all of the observations lie between what two values?

Lower Value

Upper Value