Question

Anystate Auto Insurance Company took a random sample of 356 insurance claims paid out during a 1-year period. The average claim paid was $1515. Assume o = $260. Find a 0.90 confidence interval for the mean claim payment. (Round your answers to two decimal places.) lower limit $ upper limit $ Find a 0.99 confidence interval for the mean claim payment. (Round your answers to two decimal places.) lower limit $ upper limit $

show the steps please.

Answer 1

#CI for mean is

0 (1 – 2* 2,1 + 2* Vn

Z for 0.90 CI = 1.645

0.90 CI = ( 1515 - 1.645*260/sqrt(356) ,1515 + 1.645*260/sqrt(356) )

= ( $1492.33 , $1537.67)

#Lower limit= $1492.33

#upper limit= $1537.67

----------------------------------------------------------

Z for 0.99 CI = 2.575

0.99 CI = ( 1515 - 2.575*260/sqrt(356) ,1515 +2.575*260/sqrt(356) )

= ( ,$1479.56, $1550.44 )

#Lower limit=$1479.56

#upper limit= $1550.44