Does - 3/4 + 3/5 have a positive, negative or zero sum?

g The downtime per day for a computing facility has mean 4 hours and standard deviation 0.9 hour. What assumptions must be true

Sedaia [141]

Answer:

To obtain a valid approximation for probabilities about the average daily downtime, either the underlying distribution(of the downtime per day for a computing facility) must be normal, or the sample size must be of 30 or more.

Step-by-step explanation:

Central Limit Theorem

The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean $\mu$ and standard deviation $\sigma$ , the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean $\mu$ and standard deviation $s = \frac{\sigma}{\sqrt{n}}$ .

For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.

For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean $\mu = p$ and standard deviation $s = \sqrt{\frac{p(1-p)}{n}}$

In this question:

To obtain a valid approximation for probabilities about the average daily downtime, either the underlying distribution(of the downtime per day for a computing facility) must be normal, or the sample size must be of 30 or more.

7 0

3 years ago

Determine if line AB is tangent to the circle. Type

adoni [48]

Answer:

If AB is a tangent to the circle, the triangle ABO is right angled, as the angle where a tangent meets the circumference is always 90 degrees.

We also know that Pythogoras' theorem only holds for right angled triangles.

The hypotenuse is 12 + 8 as 12 is the radius so is 20.

16^2+12^2 = 256 + 144 = 400 = 20^2 so AB must be tangent.

6 0

2 years ago

What is the value of the expression 24 + 32? Numerical Answers Expected! Answer for Blank 1: