→WILL GIVE BRAINLIEST← In a survey of adults aged 57 through 85​ years, it was found that 86.6​% of them used at least one prescription medication. Complete parts​ (a) through​ (c) below.
a. How many of the 3149 subjects used at least one prescription​ medication?

​(Round to the nearest integer as​ needed.)

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

​(Round to one decimal place as​ needed.)

a. 2,727

b. (85.6%, 87.6%)

Step-by-step explanation:

The percentage of the adults aged 57 through 85 that used at least one prescription medication = 86.6%

a. The expected number of the 3,149 subjects aged 57 through 85 that used at least one prescription medication = 3,149 × 86.6/100 = 2,727.034 ≈ 2,727 (subjects)

b. The 90% confidence interval estimate of the percentage of adults aged 57 through 85 years who use at least one prescription medication is given as follows;

Where;

= 86.6/100= 0.866

n = 3,149

z = The z-value at 90% confidence level = 1.645

Therefore, we get the following confidence interval of the percentage of adults (rounded to one decimal place as required);

The 90% confidence interval, of the percentage C.I. ≈ (85.6%, 87.6%).