Given:
Sample proportion = 85% = 0.85.
Confidence level (CL) = 90%.
Confidence interval (CI)

We want the confidence interval to be 5% or 0.05. Therefore

Because this number is less than 1, a default sample size of 30 (for the normal distribution) is recommended.
Answer: 30
h = 2

You must isolate the variable to solve using the order of operations, or PEMDAS.

Subtract 3 from both sides of the equation, and subtract 2h from both sides of the equation.

Divide both sides of the equation by 2.

Y = m x + b , where m is the slope. The slope is the rise over the run or the change in x ( rooms cleaned ) over the change in y ( cost ).
125 = m * 1 + b
175 = m * 2 + b
-----------------------
b = 125 - m
175 = 2 m + 125 - m
m = 175 - 125
m = 50 ( the rate of change ), b = 75
The formula is: y = 50 x + 75
It means that the starting cost will be $75 and that for every room cleaned, the cost will rise for $50.
Answer:
21
Step-by-step explanation:
Factored form - x= -1/2, -5/4