Answer:
4
Step-by-step explanation:
The z-score is calculated by the following formula
z=(x-μ)/σ
where
μ=Population mean
σ=Population standard deviation
If the z-score for a specific sample mean is discussed then z-score is computed as
z=xbar-μ/σxbar.
where
μ=Population mean
σxbar=Sample standard deviation
As the population mean and mean of sampling distribution of mean are equal so, μ is used in above equation.
Now, the z-score is given
1.5=xbar-μ/σxbar
σxbar=xbar-μ/1.5.
Also we know that z-score corresponds to a score that is 6 points above mean which means that xbar-μ=6.
σxbar=6/1.5
σxbar=4.
Thus, the required sample standard deviation is 4.
AB and WX because the length is directly the same
Answer:
(E) None of these above are true.
Step-by-step explanation:
Married = 74% or 0.74
College graduates = 42% or 0.42
pr(married | college graduates) = 0.56
(A) These events are pairwise disjoint. This is false. Pairwise disjoint are also known as mutually exclusive events. Here we can see that both events are occurring at same time.
(B) These events are independent events. This is also false.
(C) These events are both independent and pairwise disjoint. False
(D) A worker is either married or a college graduate always. False
Here Probability(A or B) shall be 1
= Pr(A) + Pr(B) - Pr( A and B) = 0.74 + 0.42 - 0.56 * 0.42 = 0.9248
This is not equal to 1.
(E) None of these above are true. This is true.
Answer: The proportion that will qualify is 0.0314 or 3.14%.
First, we need to find the z-score of a time of 128 seconds. To do this, we find the difference of the mean and score and divide by the standard deviation.
(128 - 141) / 7 = -1.86
Now, use a standard normal distribution table to determine the percent below a z-score of -1.86. That value is 0.0314 or 3.14%.
Answer:
The lateral surface area of the cone is 
.
Step-by-step explanation:
We have.
Height of a cone is 60 m
Diameter of a cone is 10 m
Radius, r = 80 m
The lateral surface area of a cone is given by :
l is slant height of the cone,
Plugging all values in above formula,
So, the lateral surface area of the cone is .
