Question

A USA Today/CNN/Gallup survey of 369 working parents found 200 who said they spend too little time with their children because of work commitments. a. What is the point estimate of the proportion of the population of working parents who feel they spend too little time with their children because of work commitments? b. At 95% confidence, what is the margin of error? c. What is the 95% confidence interval estimate of the population proportion of working parents who feel they spend too little time with their children because of work commitments?

Answer 1

Answer: a. 0.542

b. 0.051

c. $(0.491,\ 0.593)$

Step-by-step explanation:

Let p be the population proportion of parents spend too little time with their children because of work commitments

As per given , we have

n= 369

$\hat{p}=\dfrac{200}{369}=0.542005420054\approx0.542$

Since the sample proportion is the best estimate for the population proportion.

So , the point estimate of the proportion of the population of working parents who feel they spend too little time with their children because of work commitments = 0.542

z-value for 95% confidence interval : $z_{\alpha/2}=1.96$

Margin of error : $E=z_{\alpha/2}\sqrt{\dfrac{\hat{p}(1-\hat{p})}{n}}$

$E=(1.96)\sqrt{\dfrac{0.542(1-0.542)}{369}}\\\\=0.0508364564574\approx0.051$

The margin of error = 0.051

Confidence interval : $\hat{p}\pm E$

$0.542\pm0.051\\\\=(0.542-0.051,\ 0.542+0.051)\\\\=(0.491,\ 0.593)$

95% confidence interval estimate of the population proportion of working parents who feel they spend too little time with their children because of work commitments : $(0.491,\ 0.593)$