Question

A 90% confidence interval for the mean age, in weeks, at which a baby first crawls was reported to be (32, 46). The margin of error for this confidence interval is

Answer 1

The margin of error for a confidence interval is calculated by taking half of the width of the interval.

Step-by-step explanation:

The margin of error for a confidence interval is calculated by taking half of the width of the interval. In this case, the confidence interval is (32, 46), so the width is 46 - 32 = 14. Therefore, the margin of error is half of that, which is 14/2 = 7.

Answer 2

The margin of error for this confidence interval is of 7.

Step-by-step explanation:

Confidence interval concepts:

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 subtraction between these bounds, divided by 2.

In this question:

The bounds are 32 and 46.

(46 - 32)/2 = 14/2 = 7

The margin of error for this confidence interval is of 7.