Answer:
99.38%
Step-by-step explanation:
We have that the mean (m) is equal to 124, the standard deviation (sd) 6.4 and the sample size (n) = 64
They ask us for P (x <126)
For this, the first thing is to calculate z, which is given by the following equation:
z = (x - m) / (sd / (n ^ 1/2))
We have all these values, replacing we have:
z = (126 - 124) / (6.4 / (64 ^ 1/2))
z = 2.5
With the normal distribution table (attached), we have that at that value, the probability is:
P (z <2.5) = 0.9938
The probability is 99.38%
2x² + 3x -8 = 0
a = 2 , b = 3 , c = -8
So..
D = b²-4ac = 9 + 64 = 73
for bigger solution , use x = -b + √D / 2a
For smaller solution, use x = -b - √D / 2a
So
= -3 + √73 / 2. 2
= 1/4 (√73 -3)
Hopefully helpfull.. ^_^
Answer:
Step-by-step explanation:
We need to evaluate if thickness of a 10 gauge metal sheet is a requiered in the process that means 3.416 mm thick. So that should be our null hypothesis; μ₀ = 3.416 and based on sample data, we will formulate an alternative hypothesis taking into account the mean, and standard deviation obtained. We surely will have better information to take a decision