*Stuck on below 3 problems. Need, help... thanks.*

**1)** In a survey of 3497 adults, 1485 say they have started paying bills online in the last year.

Construct a 99% confidence interval for the population proportion. Interpret the results.

A 99% confidence interval for the population proportion is (___, ____)

(Round to three decimal places as needed.)

__________________________________________________________________________

**2) **Construct the confidence interval for the population mean μ.

C = 0.95, x = 15.6, σ = 2.0, and n = 55

A 95% confidence interval for μ is (____, _____) is

(Round to one decimal place as needed.)

_____________________________________________________________________________

**3)** A researcher wishes to estimate, with 95% confidence, the population proportion of adults who are confident with their country's banking system. His estimate must be accurate within 3% of the population proportion.

(a) No preliminary estimate is available. Find the minimum sample size needed.

(b) Find the minimum sample size needed, using a prior study that found that 32% of the respondents said they are confident with their country's banking system.

(c) Compare the results from parts (a) and (b).

(a) What is the minimum sample size needed assuming that no prior

information is available?

n = ___ (Round up to the nearest whole number as needed.)

#### Top Answer

question 1 The confidence interval for proportion is given by CI= p` + z c *sqrt(p`q`/n) Where p` is the sample proportion we... View the full answer