M varies directly with n; m=144 when n=8. What is the constant of variation k?

Question

I don't know what this mean. Could you help me out in solving this/

A statement such as
"M varies directly with n" can be changed to the equation
M=kn, where k is a constant.
since you are given the values of M and n, substitute these into that equation and you can find k

By the way, 'M varies directly with n' is also often stated as, "M is directly proportional with n"

3x=6

3x=6 x=2