Answer
margin of error = 1.4 and sample mean = 13.4
Work Step by Step
1) Find the width of the interval
14.8 - 12.0 = 2.8
2) Find the margin of error:
2.8/2 = 1.4
(Remember that the interval is formed by adding and subtracting the MOE from the mean. Hence, we divide the width by two to find how much was added on to both sides).
3) Subtract the margin of error from upper bound to find mean
14.8 - 1.4 = 13.4
Therefore, margin of error = 1.4 and sample mean = 13.4
