Nancy is a waitress at Seventh Heaven Hamburgers. She wants to estimate the average amount each table leaves for a tip. A random sample of 5 groups was taken and the amount they left for a tip (in dollars) is listed below:

$13.00

$8.00

$6.00

$3.00

$5.00

a.) Find a 90% confidence interval for the average amount left by all groups. (*round to the nearest cent*) $ < < $ b.) If the sample size were larger, with everything else remaining the same, would the margin of Error increase or decrease?

• Decrease
• Increase

c.) If the Confidence level were 95% instead of 90%, would the range (size) of the Confidence Interval be larger or smaller?

• Smaller
• Larger