Question 665796
Given
22A + 19B ≥ 2400
A + B ≤ 120
...
Substitute the second equation into the first and solve for A and B
Solve for B
22(120-B) +19B ≥ 2400
2640 - 22B +19B ≥ 2400
2640 - 2400 ≥ 22B - 19B
240 ≥ 3B
80 ≥ B
Therefore,
B &#8804 80
...
Solve for A
22A + 19(120-A) ≥ 2400
22A + 2280 - 19a ≥ 2400
22A - 19A ≥ 2400 - 2280
3A ≥ 120
A ≥ 40
Therefore,
A &#8805 40
.....
To minimize cost, order
80 of type B and 40 of type A
{{{highlight(choice2)}}}
This makes sense as type A costs more than B, 
so you would want to order less of the more expensive type.  
Opt for the maximum of B and the minimum of A.
.....................
Delighted to help.
-Reading Boosters
Wanting for others what we want for ourselves.
www.MyHomeworkAnswers.com