Which graph shows a positive relationship between variables ?

Mathematics

1 answer:

Brums [2.3K]4 years ago

5 0

Answer:

scatter-plots

Step-by-step explanation:

Scatter plots are similar to line graphs in that they use horizontal and vertical axes to plot data points. However, they have a very specific purpose. Scatter plots show how much one variable is affected by another. The relationship between two variables is called their correlation .

You might be interested in

How can you calculate the area of the circle if you know the circle’s circumference?

Nimfa-mama [501]

Divide the circumference by pi, then divide that by 2, then you would have the radius, and the area is r squared multiplied by pi

8 0

4 years ago

Grades on a standardized test are known to have a mean of 1000 for students in the US. The test is administered to 453 randomly

Mademuasel [1]

Answer:

a: 1003 < µ < 1023

b: See attached photo for answers

c: see below

d and e: See second attached photo

f: See below

Step-by-step explanation:

a. to find a confidence interval, first find the error with the formula,

E = Z(σ/√n) where Z is the value of the z-score that relates to the confidence level, σ is the standard deviation of the population (or of the sample if the population standard deviation isn't given), and n is the sample size

For this problem, E = 1.96(108/√453) = 9.95 = 10

Now add and subtract that value form the sample average...

x - E < µ < x + E becomes 1013 - 10 < µ 1013 + 10

simplifies to 1003 < µ < 1023

b. See attached photo for hypothesis test results...

c. H0: µ = 1013

Ha: µ > 1013 (claim)

They want to test if it's greater than their first attempt, so this claim becomes the alternate hypothesis. We're testing against their first attempt, that's why µ = 1013, not 1000

d and e. See second attached photo for hypothesis test results...

f. There is enough evidence to support the claim that the students second attempt was an improvement from their first attempt. They happened to take a 2 hour tutoring course between tests. This doesn't prove that the tutoring was effective thought. It very well might have been effective, but also, the students taking the test again means they've already seen the test and know what to expect, which could have also boosted their scores.