9. Find P(Z < 0). A. .9332 B. .0668 C. .5668 D. .500 10. The area under a normal
ID: 2955414 • Letter: 9
Question
9. Find P(Z < 0).
A. .9332 B. .0668
C. .5668 D. .500
10. The area under a normal curve from z value of1.00 up to a z value of 2.00 is
A. .3413
B. .4772
C. .8185
11. A normal probability distribution iscompleted described by the
A. mean only. B. variance only.
12. Find P(-1 < Z < 0).
A. -.6426 B. .6426 C. .4772
13. Find P(Z < -2.5).
A. .9332 B. .0668 C. .0062
14. Find z so that P(Z > z) = .2.
A. .25 B. -.25 C. -1.28
15. Find z so that P(-z < Z < z) =.98
A. .02 B. 2.33
C. .3365 D. .1879
16. Which of the following is NOT true regardingthe normal distribution?
A) Mean, median and mode are all equal
B) It has a single peak
C) It is symmetrical
D) The points of the curve meet the X-axis at z =-3 and z = 3
17. The mean amount spent by a family of four onfood per month is $500 with a standard deviation of $75. Assumingthat the food costs are normally distributed, what is theprobability that a family spends less than $410 permonth?
A) 0.2158 B) 0.8750
C) 0.0362 D) 0.1151
E) None of the above
Explanation / Answer
9.D. .500 10.D. None of the above. 11.C. mean and standarddeviation. 12.E. .3413 13.C. .0062 14. E. .84 15. B. 2.33 16.E) None of the above 17.D) 0.1151