Question

In a study of Math SAT scores done in 2010, the investigators computed the average Math SAT score ( A i )in each of the 50 states and D.C. and the percentage ( P i )of high school seniors in each state that took the test that year. They found that the correlation between the variables A and P was r = -0.77.

(a) Does this mean that the the test scores were better on average in states where fewer a lower percentage of students took the test? Answer yes or no, and explain your answer briefly.

(b) The average Math SAT score in NY was 515 in 2010, while in Montana, the average score was 603. Does this mean that Montana does a better job preparing students for the Math SAT exam than NY state? Answer yes or no, and explain your reasoning.

Mark the statements that are correct.

A. The correlation between the average weight (of adults) and the average height (of adults) in each state (for all 50 states and D.C.) is likely to be higher than the correlation between the weights and heights of individual adults in the U.S.

B. The correlation between the heights and weights of boys at age 6 is probably lower than the correlation between their heights and weights at age 21.

C. In a study of male college students, the correlation between weight of the student and the amount of weight that the student could lift was r ≈ 0.66.

This means that a student can grow stronger by increasing his weight.

D. A group of 8 year olds were given a basic math skills test at the beginning of the school year and then again at the end of the school year. The students who did poorly on the first test, did better on the second test, on average, than they did on the first test. Similarly, the students who did well on the first test, did not do as well on the second test.

This is likely because the weaker students got more help with math throughout the school year, while the stronger students were left more to their own devices.

E. The regression equation for predicting the weight a student could lift, based on the student's weight is

y^i=32+0.7xi,

where xiis the weight of the ithstudent and yiis the amount that the ithstudent can lift, both measured in pounds.

This means that, on average, students who weigh 160 pounds can lift 7 more pounds than students who weigh 150 pounds.

F. The correlation between girls' heights at age 6 and their heights at age 18 is probably smaller than the correlation between girls' heights at age 16 and their heights at age 18.

Answer 1

we have given that the correlation between the variables A and P was r = -0.77.

(a) Does this mean that the the test scores were better on average in states where fewer a lower percentage of students took the test\

yes it is true . this is because of there is strong negative correlation between the average Math SAT score ( A i )in each of the 50 states and D.C. and the percentage ( P i )of high school seniors in each state that took the test that year.

(b) The average Math SAT score in NY was 515 in 2010, while in Montana, the average score was 603. Does this mean that Montana does a better job preparing students for the Math SAT than NY state?

since the data not provided for part b so w cannot sau anything without data