Answer: Option 'd' is correct.
Step-by-step explanation:
Since we have given that
Margin of error = 0.5 years
Standard deviation = 5
At 90% confidence, z = 1.645
We need to find the minimum size of the sample they must take.
So,

Hence, Option 'd' is correct.
Answer:
10.9=n
Step-by-step explanation:
I think the first box is perpendicular good luck
Answer:
500
Step-by-step explanation:
15% * x = 75
(15/100) * x = 75 Multiply both sides by 100/15
(15/100)*(100/15) = 75 * 100/15
x = 7500/15
x = 500
Answer 500
Proportion
15/100 = 75 / x Cross multiply
15x = 100*75 Combine the right
15x = 7500 Divide 15
15x/15 = 7500/15
x = 500