The figure is made up of identical cubes. If the volume of the solid is 3250 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 40 cm?
(a)
Total number of cubes = 26
Volume of 1 cube
= 3250 ÷ 26
= 125 cm
3 Length of 1 side
= ³√125
= 5 cm
Area of 1 side of cube
= 5 x 5
= 25 cm
2 Number of exposed surfaces = 92
Total surface area of the figure
= 92 x 25
= 2300 cm
2 (b)
Volume of the cube with 40 cm side
= 40 x 40 x 40
= 64000 cm³
Total number of cubes
= 64000 ÷ 125
= 512
Number of more cubes needed
= 512 - 26
= 486
Answer(s): (a) 2300 cm
2; (b) 486
