A sales manager collected the following data on annual sales fornew customer accounts and the number of years of experience for asample of salespersons. Salesperson Years of Experience AnnualSales ($1000s)
1 1 80
2 2 100
3 3 106
4 4 105
5 6 111
6 8 120
7 9 121
8 11 116
9 13 136
10 14 142
The data y= on annual sales($1000s) for new customer accountsand x= number of years of experience for a sample of 10salespersons provided the estimated regression equationy=88.22+3.59x . For these data x=7.1, (xi-x)2192.90 ,and s=6.8693.
a. Develop the 95% confidence interval for the mean annual salesfor all salespersons with twelve years of experience. ( , ) (to 2decimals)
b. The company is considering hiring Tom Smart, a salespersonwith twelve years of experience. Develop a 95% prediction intervalof annual sales for Tom Smart. ( , ) (to 2 decimals)
