He will need to cut altogether 12 inches to fit on the top if h buys 2 to adjust on the double desk.
Explanation:
- Jackson building a double desk requires 120 in long.
- When each board is 66 inches
- Therefore, if he buys 2 Boards, 2 x 66 = 132
- He needs to cut . subtracting 132 - 120 to adjust on the desk.
- 132-120 = 12 if he cuts the board to adjust on each desk.