Statistics 3301

Question

In this scenario, what is the test statistic?

1. The claim is the percent of U.S. adults who owe more than $6,000 on their credit cards is less than 45%.
2. Sample size =50 U.S. adults
3. Sample proportion =0.50 
4.  

Calculate the test statistic using the formula:

z0=p′−p0p0⋅(1−p0)n−−−−−−√

1. where:p′ = sample proportion,
2. n = sample size, and 
3. p0 = population proportion under the null hypothesis

Round your answer to 2 decimal places.

Provide your answer below:

z

0 =_______

​ 

Answer 1

Use the one-proportion z-test.

p' = 0.50

p₀ = 0.45

n = 50

z = (p' - p₀) / [√p₀(1 - p₀)/n] = (0.5 - 0.45) / [√(0.45)(0.55)/50] = 0.05/0.0703 ≈ 0.71