# Statistics

posted by
**Jason L** on
.

A survey of community banks asked about the loan to deposit ratio (LTDR) a banks total loans as a percent of its total deposits. The mean LTDR for the 110 banks in the sample is xbar = 76.7 and the standard deviation is s = 12.3. In the text a 95% confidence interval (using a z score) is given for the mean LTDR for community banks. This solution is theoretically not completely correct. What should the interval be?

A -

74.6-79.2

74.38-79.02

74.3-78.9

74.28-78.88

74.2-78.8

Formula:

CI95 = mean + or - 1.96(sd divided by √n)

...where + or - 1.96 represents the 95% confidence interval using a z-table, sd = standard deviation, √ = square root, and n = sample size.

With your data:

CI95 = 76.7 + or - 1.96(12.3/√110)

Finish the calculation for your interval.