The figure shows a plastic cuboid that measures 125 m by 15 m by 15 m.
- Find the maximum number of 7-m cubes that can be cut from the plastic cuboid.
- Find the total surface area of the L-shaped block after cutting.
(a)
Number of cubes along the length
= 125 ÷ 7
= 17 r 6
Breath = Height
Number of cubes along the breadth or height
= 15 ÷ 7
= 2 r 1
Maximum number of 7 m cubes
= 17 x 2 x 2
= 68
(b)
Area of the 2 squares
= 2 x 15 x 15
= 450 m
2 Area of the top and bottom bases
= 2 x 125 x 15
= 3750 m
2 Area of 1 L-shaped side
= 125 x 1 + (15 - 1) x 6
= 125 + 84
= 209 m
2Area of 2 L-shaped sides
= 2 x 209
= 418 m
2 Total surface area
= 3750 + 450 + 418
= 4618 m
2 Answer(s): (a) 68; (b) 4618 m
2