Question 1147992
<br>
Let the number of packages be x; then the number of letters is x+15.<br>
The total cost is the delivery fee, plus $8 for each package and $3 for each letter; and the total cost has to be $85 or less.<br>
{{{10+8(x)+3(x+15) <= 85}}}<br>
{{{11x+55 <= 85}}}
{{{11x <= 30}}}<br>
In this problem, x has to be an integer; the largest integer value of x that satisfies that inequality is x=2.<br>
So the maximum number of items that can be delivered for $85 or less is<br>
{{{x + (x+15) = 2+17 = 19}}}<br>