Respuesta :
Answer:
The class interval is from (22.8748 ug/m³ - 21.1252 ug/m³).
Step-by-step explanation:
Given : Sample size(n)= 144
Sample mean [tex]\mu= 22 ug/m^3[/tex]
Standard deviation [tex]\sigma=3.5 ug/m^3[/tex]
To find : 99.7% confident that actual concentration of fine particulates at the school is?
Solution :
The formula for confidence interval is
[tex]CI=\mu \pm z\times\dfrac{\sigma}{\sqrt{n}}[/tex]
Substituting the values in the formula,
[tex]CI=22 \pm 3\times\dfrac{3.5}{\sqrt{144}}[/tex]
[tex]CI=22 \pm 3\times\dfrac{3.5}{12}[/tex]
[tex]CI=22 \pm 3\times 0.2916[/tex]
[tex]CI=22 \pm 0.8748[/tex]
[tex]CI=22+0.8748, 22-0.8748[/tex]
[tex]CI=22.8748, 21.1252[/tex]
Therefore, The class interval is from (22.8748 ug/m³ - 21.1252 ug/m³).
Answer:
21 ug/m^3 - 23 ug/m^3
Step-by-step explanation:
Just got it right
