Question

In a survey of 3396 adults aged 57 through 85​ years, it was found that 82.2​% of them used at least one prescription medication. Complete parts​ (a) through​ (c) below.

A. How many of the 3396 subjects used at least one prescription​ medication?

B. Construct a​ 90% confidence interval estimate of the percentage of adults aged 57 through 85 years who use at least one prescription medication.

?​% <p< ?%

(Round to one decimal place as​ needed.)

Choose One: A, B, C, D

What do the results tell us about the proportion of adults aged 57 through 85 years who use at least one prescription​ medication?

A.The results tell us nothing about the proportion of adults aged 57 through 85 year who use at least one prescription medication.

B.The results tell us that there is a​ 90% probability that the true proportion of adults aged 57 through 85 year who use at least one prescription medication is in the interval found in part​ (b).

C.The results tell us​ that, with​ 90% confidence, the true proportion of adults aged 57 through 85 year who use at least one prescription medication is in the interval found in part​ (b).

D.The results tell us​ that, with​ 90% confidence, the probability that a adults aged 57 through 85 year uses at least one prescription medication is in the interval found in part​ (b).

Answer 1

Given:

n = 3396, = 82.2% = 0.822

= 1- = 1-0.822 = 0.178

A)

= X/n

0.822 = X/3396

X = 3396 * 0.822

X = 2791.51 2792

Approximately 2792 of the 3396 subjects used at least one prescription​ medication?

B)

Critical value:

         …………Using standard Normal table

90% Confidence interval:

0.81 < P < 0.83

or

81.1% < P < 83.3%

ANSWER: C

C.The results tell us​ that, with​ 90% confidence, the true proportion of adults aged 57 through 85 year who use at least one prescription medication is in the interval found in part​ (b).