Answer:
a. 0.56
b. 0.262
c. 672
Step-by-step explanation:
Confidence interval:
A confidence interval has two bounds, a lower bound and an upper bound.
A confidence interval is symmetric, which means that the point estimate used is the mid point between these two bounds, that is, the mean of the two bounds.
The margin of error is the result of the subtraction between these two bounds divided by 2.
a. The point estimate of the population proportion is
Mean of the bounds. So
(0.298 + 0.822)/2 = 0.56
b. The margin of error is
(0.822-0.298)/2 = 0.262
c. The number of individuals in the sample with the specified characteristic is
0.56 of 1200. So
0.56*1200 = 672