B = {x|x ∈ N and 1 ≤ x < 9}

You are constructing a histogram for scores that range from 70 to 100 in whole points. frequencies range from 3 to 10; that is, every whole-point score between 60 and 100 occurs at least 3 times, and at least one score occurs 10 times. which of these would probably be the best range and size for the score intervals along the x-axis?

If the cost to mail a package is an initial $5 and $0.28 for every pound the total cost to mail a package was $11.27, how much did the package weigh?

Which equation results from adding the equations in this system? x+6y=9 and -x+2y=-15