0.85 Source: Based on B. Groysberg, P. Healy, and C. Chapman, Financial Analysis Journal, Vol. 64, No. 4, July/August 2008. 4.103 Blood diamonds. According to the World Diamond Council (2020), 1% of all rough diamonds produced in the world are blood diamonds, i.e., diamonds mined to finance war or an insurgency. In a random sample of 700 rough diamonds purchased by a diamond buyer, let x be the number that are blood diamonds.

a. Find the mean of x.

b. Find the standard deviation of x.

c. Find the z-score for the value x = 10.

d. Find the approximate probability that the number of the 700 rough diamonds that are blood diamonds is less than or equal to 10. M04_MCCL3396_14_GE_C04.indd 258 29/09/2021 14:01 SECTION 4.6 ● The Normal Distribution 259 4.104 Job satisfaction. Refer to the Randstad Workmonitor data on job satisfaction, Exercise