Answer:
9 boxes were packed. 10 brownies were left over.
Step-by-step explanation:
127 ÷ 13 = 9 R10
13 x 9 = 10 x 9 + 3 x 9 = 90 + 27 = 117
127 - 117 = 10
The correct answer is A.
You have direct variation if x and y are modeled by the equation

In this case, m is the constant of proportionality. So, if the constant has to be 2, the equation becomes

A side note: Actually, option C has a constant of proportionality of two as well, except the roles of x and y are interchanged. I chose option A because usually you want the y = mx form, but the names of the variables are obviously meaningless.
2(12+18) is not equivalent to 24+18