The figure is made up of identical cubes. If the volume of the solid is 1664 cm
3,
- find the total surface area of the figure.
- how many more of such cubes is to be added to form a cube of side 28 cm?
(a)
Total number of cubes = 26
Volume of 1 cube
= 1664 ÷ 26
= 64 cm
3 Length of 1 side
= ³√64
= 4 cm
Area of 1 side of cube
= 4 x 4
= 16 cm
2 Number of exposed surfaces = 92
Total surface area of the figure
= 92 x 16
= 1472 cm
2 (b)
Volume of the cube with 28 cm side
= 28 x 28 x 28
= 21952 cm³
Total number of cubes
= 21952 ÷ 64
= 343
Number of more cubes needed
= 343 - 26
= 317
Answer(s): (a) 1472 cm
2; (b) 317