Answer:
We need a sample of size at least 13.
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of
, and a confidence level of
, we have the following confidence interval of proportions.

In which
z is the zscore that has a pvalue of
.
The margin of error is:

90% confidence interval: (0.438, 0.642).
The proportion estimate is the halfway point of these two bounds. So

95% confidence level
So
, z is the value of Z that has a pvalue of
, so
.
Using the information above, what size sample would be necessary if we wanted to estimate the true proportion to within ±0.08 using 95% confidence?
We need a sample of size at least n.
n is found when M = 0.08. So






Rounding up
We need a sample of size at least 13.
Answer: 3/20
Step-by-step explanation:
12/80 is simplified to 3/20
Answer:
-8a^2 + 9a
or
9a - 8a^2
the answer is c
Step-by-step explanation:
10 yellow cards over 30 = 10/30
second selection : 9 yellow cards over 29 = 9/29
10/30 * 9/29 = 1/3 * 9 /29 = 3/29 = 0.1034 = 10.34%
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