Answer:
9
Step-by-step explanation:
This is because 21/7 is 3. So, you use the scale factor of 3 to divide 27/3 to get x which is 9.
Answer: The 95% confidence interval is approximately (55.57, 58.43)
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Explanation:
At 95% confidence, the z critical value is about z = 1.960 which you find using a table or a calculator.
The sample size is n = 17
The sample mean is xbar = 57
The population standard deviation is sigma = 3
The lower bound of the confidence interval is
L = xbar - z*sigma/sqrt(n)
L = 57 - 1.960*3/sqrt(17)
L = 55.5738905247863
L = 55.57
The upper bound is
U = xbar + z*sigma/sqrt(n)
U = 57 + 1.960*3/sqrt(17)
U = 58.4261094752137
U = 58.43
Therefore the confidence interval (L, U) turns into (55.57, 58.43) which is approximate.
Answer:
18 hours
Step-by-step explanation:
15 centimeters -> 6 hours
Multiply by 3
45 centimeters -> 18 hours
Sqrt(49)*sqrt (-1) -4 = 7i-4