# Interval Estimation & Margin of Error

# 1. use the sample data and confidence level to construct the confidence interval estimate of the population proportion p.

n= 550, x= 440, 95% confidence

< p <

#2 use the given confidence level and sample data to find (a) the margin of error and (b) the confidence interval for the population mean m. assume that the population has a normal distribution .

Weight lost on a diet 99% confidence ; n = 61 xbar= 4.0kg, s= 5.8 kg

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Solving these problems

1. Use the sample data and confidence level to construct the confidence interval estimate of the population proportion p.

n= 550, x= 440, 95% confidence

< p <

Answer

90% Confidence Interval for proportion is given by

where p = x/n = 440/550 = 0.80, = 1.959963985, n = 550

= (0.767, 0.833)

= 0.767 < p < 0.833

Thus with 95% confidence we can claim that the population proportion is within (0.767, ...

#### Solution Summary

The solution provides step by step method for the calculation of confidence interval for population mean and population proportion and margin of error. Formula for the calculation and Interpretations of the results are also included. Interactive excel sheet is included. The user can edit the inputs and obtain the complete results for a new set of data.