Question #1

Find the critical value z_/2 that corresponds to the given confidence level.

91%

z_/2 = __________

(Round to two decimal places as needed.)

Question #2

Salaries of 32 college graduates who took a statistics course in college have a mean, x,

of $66,900. Assuming a standard deviation, , of $12,707, construct a 99% confidence interval for estimating the population mean .

View a t distribution table.

NEGATIVE z Scores Standard Normal (2) Distribution: Cumulative Area from the LEFT 03 -350 mid 0003 03012 5003 -14 -13 10005 -11 -32 DOOT DOOT 6010 -10 -3.1 -29 -310 0013 8013 DO13 0015 0019 -29 0325 DO24 6035 0045 5049 -25 -24 -21 -23 -21 -20 -1.7 -18 IIIIIIIIIIII -13 -17 -LI 1511 2451 -05 -QA Jrar 3197 -02 AM -01 5000 BPOSITIVE z Scores Cumulative Area from the LEFT 05 01 5270 5319 6349 5000 5060 5120 ST14 5753 6506 5438 5517 8141 02 5812 SATI 5010 6440 0.3 6179 6217 04 4736 8772 6584 0.5 7123 F157 7190 7224 6915 7480 7549 7353 1422 7257 7794 7852 7611 7673 3704 T764 7967 8051 6821 1.0 8413 1.1 9015 12 9131 9162 13 0304 0515 9584 1.8 1671 9732 9744 9767 0812 20 21 9821 5842 22 9801 9471 24 25 25 28 27 9573 9985 9090 30 9091 9016 9597 3.50 and up 3:50 and up 104 07