The figure shows a wooden cuboid that measures 142 m by 15 m by 15 m.
- Find the maximum number of 9-m cubes that can be cut from the wooden cuboid.
- Find the total surface area of the L-shaped block after cutting.
(a)
Number of cubes along the length
= 142 ÷ 9
= 15 r 7
Breath = Height
Number of cubes along the breadth or height
= 15 ÷ 9
= 1 r 6
Maximum number of 9 m cubes
= 15 x 1 x 1
= 15
(b)
Area of the 2 squares
= 2 x 15 x 15
= 450 m
2 Area of the top and bottom bases
= 2 x 142 x 15
= 4260 m
2 Area of 1 L-shaped side
= 142 x 6 + (15 - 6) x 7
= 852 + 63
= 915 m
2Area of 2 L-shaped sides
= 2 x 915
= 1830 m
2 Total surface area
= 4260 + 450 + 1830
= 6540 m
2 Answer(s): (a) 15; (b) 6540 m
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