Answer:
slope = - 
Step-by-step explanation:
Calculate the slope m using the slope formula
m = 
with (x₁, y₁ ) = (- 5, 7 ) and (x₂, y₂ ) = (2, 5 )
m =
=
= - 
Take 2 points: (0, 70) (30, 80)
SLOPE FORMULA: y2 -y1 / x2 - x1
y2 - y1: 80 - 70 = 10
x2 - x1: 30-0 = 30
10 / 30
simplify: 1/3
This is a PROPER FRACTION
Question:
You are interested in estimating the the mean age of the citizens living in your community. In order to do this, you plan on constructing a confidence interval; however, you are not sure how many citizens should be included in the sample. If you want your sample estimate to be within 5 years of the actual mean with a confidence level of 97% , how many citizens should be included in your sample? Assume that the standard deviation of the ages of all the citizens in this community is 18 years.
Answer:
61.03
Step-by-step explanation:
Given:
Standard deviation = 18
Sample estimate = 5
Confidence level = 97%
Required:
Find sample size, n.
First find the Z value. Using zscore table
Z-value at a confidence level of 97% = 2.17
To find the sample size, use the formula below:





Sample size = 61.03
I am going to do this problem with more of an algebraic approach weather or not its the way your teacher wants you to do it like this.
The way to do things algebraically is to just set variables for what you want to find and set up equations to represent each sentence.
As seen there are hamburgers and chickens in this problem. So let's set the numbers of hamburgers to x, and the numbers of chickens to y.
Now write out each sentence using variables.
1.) Tia sold 78 hamburgers and chicken tenders.
x+y=78
2.) If she sold 24 more hamburgers than chicken tenders.
x=y+24
Now that we have the 2 equations, its time to solve.
Since we have x=y+24, we can replace the x in the first equation with the second equation
y+24+y=78
2y+24=78
Now we can subtract 24 from both sides.
2y=54
Simplify
y=27
Solve for x
x=27+24=51
Done!