Answer:
Test statistic = z = 1.01264
Step-by-step explanation:
p = 0.25
q = 1 - p = 0.75
n = 520
x = 140
[tex]psample = \frac{x}{n} = \frac{140}{520} = 0.26923[/tex]
[tex]z = \frac{psample - p}{\sqrt{\frac{p*q}{n} } } =\frac{0.26923 - 0.25}{\sqrt{\frac{0.25 * 0.75 }{520} } } = \frac{0.01923}{\sqrt{\frac{0.1875}{520} } } = \frac{0.01923}{\ 0.01899} = 1.01264[/tex]