Answer:
15 ounces.
Explanation:
The first ounce is worth 0.40, and the additional x ounces are worth 0.25 each. So, the inequality should be Y > A + B * X, where Y is equal to 4, A is the value of the first ounce (0.4), B is the value of the additional ounces (0.25) and x is the quantity of additional ounces.
14 is the maximum of additional ounces that can be mailed, we have to add the first one, for a total of 15 whole ounces that can be mailed for no more than $4.