Answer:
Marla didn't use the right steps to complete the square. Maria made a mistake in step 1, she put 8x instead of -2x
Step-by-step explanation:
we have
This is a vertical parabola open downward
The vertex is a maximum
Find the vertex
step 1
Factor the leading coefficient -4
step 2
Complete the square
step 3
step 4
Rewrite as perfect squares
the vertex is the point (1,-21)
so
The maximum value of the quadratic equation is (1,-21)
therefore
Marla didn't use the right steps to complete the square. Maria made a mistake in step 1, she put 8x instead of -2x
25 is the answer..............
Answer:
a. Scatterplot is attached.
b. Positive Correlation
c. Correlation coefficient=0.9219
Step-by-step explanation:
a.
The following procedure will be used to obtain the scatter plot
- Open an Google Sheets file online or excel sheet on your computer.
- In column B and C, enter the Income and Vacation data as provided above.
- Select the data > click on insert CHART.
- Chose Scatter Chart option
A scatter plot visualizing your data should be displayed as attached.
b.
- On your computer, open a spreadsheet in Google Sheets.
- Double-click on your scatter plot.
- At the right, click on Customize tab and then Series.
- Scroll down and check the Trend line box
-From the trend line, your notice that your variables have a positive correlation.
-As the income increases, so does vacation expenditure.
c. The correlation coefficient can be calculated as follows.
- Click on any empty cell in the sheet and enter the formula
- "=CORREL((y-axis range),(x-axis range))"
- ENTER
-From our Google Sheets calculation our variables have a positive correlation and the correlation coefficient is 0.9219
-The correlation coefficient,r can also be calculated manually:
-let x be income, and y be vacation and divide all the values by 100 to make the smaller and easier to manipulate:
![r=\frac{n(\sum xy)-(\sum x)(\sum y)}{\sqrt{[n\sum x^2-(\sum x)^2][n\sum y^2-(\sum y)^2}}\\\\\\\sum xy=153914\\\sum x=4485\\\sum y=246\\\sum x^2=2878447\\(\sum x)^2=4485^2=20115225\\(\sum y)^2=246^2=60516\\\sum y^2=8392\\n=8\\\\\#substitute \ and \ solve \ for \ r\\\\=\frac{8\times153914-4485\times 246}{\sqrt{[8\times 2878447-4485^2][8\times 8392-246^2]}}\\\\=0.92186\\\\\approx 0.9219](https://tex.z-dn.net/?f=r%3D%5Cfrac%7Bn%28%5Csum%20xy%29-%28%5Csum%20x%29%28%5Csum%20y%29%7D%7B%5Csqrt%7B%5Bn%5Csum%20x%5E2-%28%5Csum%20x%29%5E2%5D%5Bn%5Csum%20y%5E2-%28%5Csum%20y%29%5E2%7D%7D%5C%5C%5C%5C%5C%5C%5Csum%20xy%3D153914%5C%5C%5Csum%20x%3D4485%5C%5C%5Csum%20y%3D246%5C%5C%5Csum%20x%5E2%3D2878447%5C%5C%28%5Csum%20x%29%5E2%3D4485%5E2%3D20115225%5C%5C%28%5Csum%20y%29%5E2%3D246%5E2%3D60516%5C%5C%5Csum%20y%5E2%3D8392%5C%5Cn%3D8%5C%5C%5C%5C%5C%23substitute%20%5C%20and%20%5C%20solve%20%5C%20for%20%5C%20r%5C%5C%5C%5C%3D%5Cfrac%7B8%5Ctimes153914-4485%5Ctimes%20246%7D%7B%5Csqrt%7B%5B8%5Ctimes%202878447-4485%5E2%5D%5B8%5Ctimes%208392-246%5E2%5D%7D%7D%5C%5C%5C%5C%3D0.92186%5C%5C%5C%5C%5Capprox%200.9219)
Answer: if he drives the car each month, he would spend $150 lesser than when he drives the truck.
Step-by-step explanation:
The car goes 25 miles on 1 gallon of gas. Jamaica drives 1000 miles per month, it means that the number of gallons of gas that he would use in a month is
1000/25 = 40 gallons of gas
If gasoline costs $2.50 per gallon and Jamaica chooses to buy a car, the cost of gas per month would be
2.5 × 40 = $100
The truck goes 10 miles on 1 gallon of gas. Jamaica drives 1000 miles per month, it means that the number of gallons of gas that he would use in a month is
1000/10 = 100 gallons of gas
If gasoline costs $2.50 per gallon and Jamaica chooses to buy a truck, the cost of gas per month would be
2.5 × 100 = $250
The difference between both costs is
250 - 100 = $150
Answer:
The wagon can hold 32 newspapers
Step-by-step explanation:
