Step 1. Set up the LP-formulation on Excel
 
A
B
C
D
1
 Profit =40*X1+30*X2
2
 Buckle A =X1 <= 400
3
 Buckle B =X2 <= 700
4
 Leather =X1+X2 <= 800
5
 Labor =X1+2*X2 <= 1000
W
X
1
 Belt A
2
 Belt B

Step 2. Click Tools, then click Solver

Step 3. Set Target Cells: B1

Step 4: By Changing cells: X1:X2

Step 5: Subject to the Constraints:

B2 <= D2
B3 <= D3
B4 <= D4
B5 <= D5
Step 5. Click Options, then choose Assume Linear Model

and Assume Non-Negative

Step 6. Click Solve

Step 7. Click Answer and Sensitivity under Reports