Answer:
b = 7
Step-by-step explanation:
-144 = 8(3-3b)
-18 = 3-3b
-21 = -3b
b = 7
4232 divided by 18 equals 235.1
Answer:
Margin of error = 0.773
Step-by-step explanation:
We are given the following information in the question.
Sample size, n = 20
Sample mean = 8
Sample standard deviation = 2
90% Confidence interval
Putting the values, we get,
Margin of error:
Putting the values, we get,
Answer:
0.324
Step-by-step explanation:
Given that :
Success rate = 30%
p = 30% = 0.3
q = 1 - p = 1 - 0.3 = 0.7
Number of trials, n = 6
Probability of having exactly 2 successes ; x = 2
P(x = 2)
Usibgbtge binomial probability relation :
P(x = x) = nCx * p^x * q^(n-x)
P(x = 2) = 6C2 * 0.3^2 * 0.7^4
P(x = 2) = 15 * 0.3^2 * 0.7^4
P(x = 2). = 0.324135
P(x = 2) = 0.324
Answer:
Answer is c
Step-by-step explanation:
In hypothesis testing whether to accept or reject null hypothesis, normally we find one method as using confidence interval. If the test statistic lies within confidence interval, we accept otherwise we reject.
For arriving confidence intervals we add and subtract margin of error from the mean we use in null hypothesis.
Margin of error = std error * critical value of test (Z or t etc)
For the same std deviation, std error = std dev/sq rt of sample size
Thus std error is inversely proportional to the square root of sample size.
If n becomes larger, std error becomes smaller and vice versa.
So margin of error increases for smaller sample size.
Since we have to select confidence level from a small sample, we have to select one which has the greatest margin of error=18
Hence answer is
c) 71%(+/-18%)
