Which number sentences show ways to solve the problem?

the 9 members of a conservation club purchased a total of 45 tree saplings. each member bought the same number of trees to plant in the community. each tree cost $15. how much did each member pay for the trees?

choose all answers that are correct.

a.
15 × 9 = 135 and 135 – 75 = 60

b.
3 × 15 = 45 and 45 + 15 = 60

c.
45 ÷ 9 = 5 and 5 × 15 = 75

d.
45 × 15 = 675 and 675 ÷ 9 = 75

must choose more than one answer

Use a calculator to verify that σ(x) = 62, σ(x2) = 1034, σ(y) = 644, σ(y2) = 93,438, and σ(x y) = 9,622. compute r. (enter a number. round your answer to three decimal places.) as x increases from 3 to 22 months, does the value of r imply that y should tend to increase or decrease? explain your answer. given our value of r, y should tend to increase as x increases. given our value of r, we can not draw any conclusions for the behavior of y as x increases. given our value of r, y should tend to remain constant as x increases. given our value of r, y should tend to decrease as x increases.