Answer: z equals 0.60 minus 0.72 all over the square root of the quantity 0.72 times 0.28 over 80
Step-by-step explanation:
let p be the population proportion of students complete their homework on a daily basis.
As per given , we have
p= 0.72
sample size : n= 80
Sample proportion : [tex]\hat{p}=0.60[/tex]
Test statistic for proportion:
[tex]z=\dfrac{\hat{p}-p}{\sqrt{\dfrac{p(1-p)}{n}}}[/tex]
i.e.
[tex]z=\dfrac{0.60-0.72}{\sqrt{\dfrac{0.72(1-0.72)}{80}}}[/tex]
i.e.
[tex]z=\dfrac{0.60-0.72}{\sqrt{\dfrac{0.72(0.28)}{80}}}[/tex]
That is , z equals 0.60 minus 0.72 all over the square root of the quantity 0.72 times 0.28 over 80
