The answer is -7+19i because of the procedure used in math
<span>Answer:
n=64 is large enough to use a z-test. The two-tailed 90% confidence interval (5% in each tail) is
pop. mean +/- 1.64 (s.d. / sqrt(n) ) = 16 +/- 1.64 * 0.2/8 oz = [15.959, 16.041]oz
m</span>
Let
L=event that a selected worker has low risk
H=event that a selected worker has high risk
We need to find
P(HL)+P(LH)
=5*20/(25*24)+20*5/(25*24)
=1/6+1/6
=1/3