Which of the following relationships represents a positive correlation between two variables?
A. As a student’s class attendance decreases, the student’s overall grade remains the same
B. As the number of hours a person exercises decreases, the weight of that person increases
C. As the number of miles driven increases, the amount of the gasoline in the tank decreases
D. As the amount of water plant receives increases, the growth rate of the plant increase.
Correlation of two variables falls into:
Positive correlation: an increase in one variable causes another variable to increase
Negative correlation: an increase in one variable causes another one to decrease
No correlation: a change in one variable does not cause any response in another variable.
From the given choices
Option a is no correlation
Option b is a negative correlation
Option c is a negative correlation
Option d is a positive correlation
Therefore, the Correct Answer is D.
More Questions on TEAS 7 Math
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Q #1: A bucket can hold 3 L. How many ml can the bucket hold?
A. 3000 mL
B. 300 mL
C. 30 mL
D. 0.003 mL
Answer Explanation
to change L to mL we use the following options of interconversions:
Or
Since we are needed to change L to mL, use the second option.
Thus, a bucket can hold 3000 mL which is equal to 3 L.
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Q #2: The scatter plot below shows the relationship between the number of hours a student listens to music and the student’s test scores. Which of the following types of correlation is shown on the scatter plot?
A. Positive
B. Positive and negative
C. No correlation
D. Negative
Answer Explanation
scatter plots can of three types: positive, negative and no correlation. A positive correlation scatter plot shows that as one variable increase, the other variable increases. A positive correlation can be visually depicted below.
In a negative correlation, the change in one variable is inversely proportional to another variable. That is, as one variable increases, the other variable decreases as shown below.
The third type of scatter plot is a no-correlation scatter plot. In this type of plot, there is no defined relationship between one variable and another one as in the curve below.
If we look at the relationship between the time the student listens to music and his test score, it is evident that no relationship exists between the two variables. Thus, this is a type of no correlation scatter plot.
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Q #3: Lana has $60. She spends 80% of the money. She then invests the remaining amount and earns a profit of 80%. How much money does she now have?
A. $21.60
B. $86.40
C. $9.60
D. $60
Answer Explanation
we are needed to find the amount Lana is left with after spending and investing the rest using the given information.
Amount Lana spends = 80% of $60= 80/100 * 60 = $48
Amount left to invest = $(60-48) = $12
Lana is left with $12, which she invests and earns a profit of 80%.
Profit earned = 80% of $12 = 80/100 * 12 = $9.20
So, Lana will have $12 + $9.20 = $21.60
