A) Sqrt(4^(2/3x)) * 2^x = 1
4^(1/3x) * 2^x = 1
2^(2/3x) * 2^x = 1
2^(5/3x) = 1
Log(2)1 = 5/3x
0 = 5/3x
x = 0
4/50 as a decimal is .08
Divide 4 by 50
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.
Your formula for this is

and

. Get everything on one side of the equals sign, set it equal to 0 and factor. When you do this you get (x-3)(x+27). The Zero Product Property rule tells us that either x-3 = 0 or x+27 = 0 and that x = 3 and -27. The only thing in math that will NEVER be negative besides time is distance/length, therefore, x cannot be 27 and has to be 3.
There is more than one way to solve this.
250° : 50min.
You can divide each side by ten for 5 minutes.
50/10 = 5 minutes
250/10 = 25°