Surface area and nets
The question
cm²
Surface area of a 7 × 10 × 13 box
How it works.
7 × 10 × 13 cm
front and back:2 × 7 × 13 =182
front and back:2 × 7 × 13 =182
the two sides:2 × 10 × 13 =260
front and back:2 × 7 × 13 =182
the two sides:2 × 10 × 13 =260
top and bottom:2 × 7 × 10 =140
front and back:2 × 7 × 13 =182
the two sides:2 × 10 × 13 =260
top and bottom:2 × 7 × 10 =140
total:582
- 01
A box has six faces, but the drawing shows only three. They come in three matching pairs.
- 02
Front and back are 7 by 13, so that pair is 2 × 7 × 13 = 182.
- 03
The two sides are 10 by 13, so that pair is 2 × 10 × 13 = 260.
- 04
Top and bottom are 7 by 10, so that pair is 2 × 7 × 10 = 140.
- 05
Add the three pairs: 182 + 260 + 140 = 582 square cm.