Answer:
112
Step-by-step explanation:
Margin of error formula:
ME = z * (Sigma) / √ n
z = 1.96 for a 95 % confidence interval;
Sigma = 3 ( the population standard deviation )
n = 500
ME = 1.96 * 3 / √500 =
= 1.96 * 3 / 22.36 =
= 5.88 / 22.36 = 0.263
Answer:
The margin error for a 95% confidence interval is 0.263.
Answer:
33.3%
Step-by-step explanation:
Let's say the percent change is x%. Then the equation is:
30 + x% * 30 = 40
Subtract 30 from both sides:
x% * 30 = 10
Divide by 30:
x% = 10/30 = 1/3
Remember that % simply means "out of 100", so:
x/100 = 1/3
Multiply both sides by 100:
x = (1/3) * 100 = 33.3%