The figure shows a rubber cuboid that measures 145 m by 30 m by 30 m.
- Find the maximum number of 4-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
= 145 ÷ 4
= 36 r 1
Breath = Height
Number of cubes along the breadth or height
= 30 ÷ 4
= 7 r 2
Maximum number of 4 m cubes
= 36 x 7 x 7
= 1764
(b)
Area of the 2 squares
= 2 x 30 x 30
= 1800 m
2 Area of the top and bottom bases
= 2 x 145 x 30
= 8700 m
2 Area of 1 L-shaped side
= 145 x 2 + (30 - 2) x 1
= 290 + 28
= 318 m
2Area of 2 L-shaped sides
= 2 x 318
= 636 m
2 Total surface area
= 8700 + 1800 + 636
= 11136 m
2 Answer(s): (a) 1764; (b) 11136 m
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