Question

Ten samples of a process measuring the number of returns per 100 receipts were taken for a local retail store. The number of returns were 10, 9, 11, 7, 3, 12, 8, 4, 6, and 11. Find the standard deviation of the sampling distribution for the p-bar chart. 0.0863 0.081 0.0273 There is not enough information to answer the question. 8.1

Answer 1

0.0273

Explanation:

np n

10 100

9 100

11 100

7 100

3 100

12 100

8 100

4 100

6 100

11 100

pbar=sumnp/sumn

pbar=10+9+11+7+3+12+8+4+6+11/10+10+10+10+10+10+10+10+10+10

pbar=81/1000

pbar=0.081

nbar=sumn/k=1000/10=100

`Standard deviation for pbar chart=\sqrt{(pbar(1-pbar))/(nbar) }`

`Standard deviation for pbar chart=\sqrt{(0.081(0.919))/(100) }`

`Standard deviation for pbar chart=\sqrt{(0.0744)/(100) }`

`Standard deviation for pbar chart=√(0.0007444 )`

Standard deviation for p-chart=0.0273