If postage costs are 22 cents for the first ounce and 17 cents for each additional ounce, what is the cost of postage for a letter weighing 3 ounces?

73 cents because you multiply 17 by 3 then you add 22 and get 73

answer: 1) twenty-seven times y

              2) twenty-seven multiplied by y

the direct variation says that:

then the equation is of the form is given by:

            where k is the constant variation.

from the given table:

consider any value of x and m(x)=y

x = 2 and m(x)=y = 3

substitute these value in [1]; we have;

divide both sides by 2 we get;

⇒

check:

put x = -1 and m(x) = -1.5

substitute in the equation:

-1.5 = -1.5                   true

therefore, the function m(x) represents a direct variation

graph of this function as shown below: