Question

A population proportion is 0.3. A sample of size 300 will be taken and the sample proportion p will be used to estimate the population proportion. Round your answers to four decimal places.

a. What is the probability that the sample proportion will be within ±0.02 of the population proportion?

b. What is the probability that the sample proportion will be within ±0.07 of the population proportion?

Many drugs used to treat cancer are expensive. BusinessWeek reported on the cost per treatment of Herceptin, a drug used to treat breast cancer (BusinessWeek, January 30, 2006). Typical treatment costs (in dollars) for Herceptin are provided by a simple random sample of 10 patients.

4,384	5,562	2,717	4,937	4,479
4,787	6,450	4,127	4,239	3,818

1. Develop a point estimate of the mean cost per treatment with Herceptin (to 2 decimals).
   $
   
2. Develop a point estimate of the standard deviation of the cost per treatment with Herceptin (to 2 decimals).
   $

How large a sample should be selected to provide a 95% confidence interval with a margin of error of 7? Assume that the population standard deviation is 20.

In an article about investment alternatives, Money magazine reported that drug stocks provide a potential for long-term growth, with over 54% of the adult population of the United States taking prescription drugs on a regular basis. For adults age 65 and older, 83% take prescription drugs regularly. For adults age 18 to 64, 45% take prescription drugs regularly. The age 18–64 age group accounts for 83.7% of the adult population (Statistical Abstract of the United States, 2008).

Round your answers to 4 decimal places.

a. What is the probability that a randomly selected adult is 65 or older?

b. Given an adult takes prescription drugs regularly, what is the probability that the adult is 65 or older?

Answer 1

( 1 )

(2 )

Create the following table.

data	data-mean	(data - mean)2
4384	-166	27556
5562	1012	1024144
2717	-1833	3359889
4937	387	149769
4479	-71	5041
4787	237	56169
6450	1900	3610000
4127	-423	178929
4239	-311	96721
3818	-732	535824

Find the sum of numbers in the last column to get.

∑(xi−X bar)²=9044042