The figure shows a rubber cuboid that measures 129 m by 18 m by 18 m.
- Find the maximum number of 5-m cubes that can be cut from the rubber cuboid.
- Find the total surface area of the L-shaped block after cutting.
(a)
Number of cubes along the length
= 129 ÷ 5
= 25 r 4
Breath = Height
Number of cubes along the breadth or height
= 18 ÷ 5
= 3 r 3
Maximum number of 5 m cubes
= 25 x 3 x 3
= 225
(b)
Area of the 2 squares
= 2 x 18 x 18
= 648 m
2 Area of the top and bottom bases
= 2 x 129 x 18
= 4644 m
2 Area of 1 L-shaped side
= 129 x 3 + (18 - 3) x 4
= 387 + 60
= 447 m
2Area of 2 L-shaped sides
= 2 x 447
= 894 m
2 Total surface area
= 4644 + 648 + 894
= 6186 m
2 Answer(s): (a) 225; (b) 6186 m
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