15 In a random sample of adults aged from 2020 the middle 95

15. In a random sample of adults aged from 20-20, the middle 95% of the men are between 168 and 191 cm tall, and the middle 95% of the women are between 155 and 174 cm tall. The heights for each sex follow a normal distribution. Robert and Amanda are each 25 years old, and Robert is 12.7 cm taller than Amanda. Which of the following is NOT a valid pair of z-scorez for the couples? Circle your answer.
Robert: z=-1.0087
Amanda: z=-0.7368
Robert: z=0.1739
Amanda: z=0.8842
Robert: z=0.556
Amanda: z=1.1579
Robert: z=1.4261
Amanda: z=2.211
16. A polling company produces a poll with a 5% margin of error. How many additional people must they survey to reduce the margin of error to no more than 3%?

Solution