Answer:
6 : 1
Step-by-step explanation:
b - 3a / 9 = a /3
Cross multiply
3(b - 3a) = 9a
Expand
3b - 9a = 9a
Add 9a to both sides
3b = 9a + 9a
3b = 18a
Divide both sides by 3
b = 6a
Ratio of a : b
6 : 1
|13-6| < x < |13+6|
So the range will be:
7 < x < 19
Answer:
Copy all that then paste it to Google and there is a site that I found the answer on but I can't copy it it's to long.
4b. Laura has a 12-foot ladder. The safety instructions recommend the
base of the ladder be placed 4 feet from the base of the wall. How highwill the ladder be able to reach on the wall? WRITE YOUR ANSWER AS A SIMPLIFIED RADICAL. (HINT: Use the abbreviation sqrt to mean "square root of." For example an answer might look like 5sqrt3, and be read "five times the square root of 3".)
Part a)
The simple random sample of size n=36 is obtained from a population with

and

The sampling distribution of the sample means has a mean that is equal to mean of the population the sample has been drawn from.
Therefore the sampling distribution has a mean of

The standard error of the means becomes the standard deviation of the sampling distribution.

Part b) We want to find

We need to convert to z-score.

Part c)
We want to find

We convert to z-score and use the normal distribution table to find the corresponding area.

Part d)
We want to find :

We convert to z-scores and again use the standard normal distribution table.
