A desk has three drawers. Each drawer is 50cm in length, 45cm in width and 0.7dm in depth. How many boards should be used to make the desk drawer?

A desk has three drawers. Each drawer is 50cm in length, 45cm in width and 0.7dm in depth. How many boards should be used to make the desk drawer?

Note that the drawer has no cover
0.7dm=7cm
50 × 45 + (50 × 7 + 45 × 7) × 2 = 3580 (cm2)
3580 × 3 = 10740 (cm2)