Answer:
The 90% confidence interval would be given by (63.330;81.070)
Step-by-step explanation:
A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".
The margin of error is the range of values below and above the sample statistic in a confidence interval.
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
Let put some notation
x=left arm , y = right arm
x: 175 169 182 146 144
y: 102 101 94 79 79
Since the Confidence is 0.90 or 90%, the value of a = 0.1 and a/2= 0.05we can use excel, a calculator or a table to find the critical value. The excel command would be: "=-T.INV(0.05,4)".And we see that ta/2= 2.13
