a bank manager wants to know the mean amount of mortgage paid per month by homeowners in an area. a random sample of 120 homeowners from this area showed that they pay an average of $1575 per month for their mortgages. the population standard deviation of such mortgages is $215. fins a 97% confidence interval for the mean amount of mortgage paid per month by all homeowners in this area.

Answer: [ 1,532.41, 1,617.59]Step-by-step explanation:Data provided :Sample size, n = 120Mean = $1,575Standard deviation = $215Confidence level = 97%Now,Confidence interval = Mean ± [tex]z\frac{\sigma}{\sqrt n}[/tex]also, for 97% confidence level z score = 2.17   [from standard z-table]= $1,575 ± [tex]2.17\frac{215}{\sqrt {120}}[/tex]= $1,575 ± 42.59Therefore,Confidence interval = [ $1,575 - 42.59, $1,575 + 42.59]= [ 1,532.41, 1,617.59]