13
A cuboid has dimensions 8 cm × 10 cm × 12 cm. It is cut into small cubes of side 2 cm. What is the percentage increase in the total surface area?
- A286.2
- B314.32
- C250.64
- D386.5
Answer not set
Discussion 1
Log in or create a free account to reply and vote.
0
CCommunity
Volume of cuboid = 8 cm x 10 cm x 12 cm = 960 cm
Total surface area of cuboid = 2 × (lb + bh + hl)
⇒ total surface area. = 2 × (8 × 10 + 10 × 12 + 12 × 8) = 592
Let the number of small cubes formed be x
⇒ Volume of cubes = x × (volume of a cube) = 8x
? Volume of cubes = Volume of cuboid
⇒ 8x = 960
⇒ x = 120 (number of cubes formed)
Total surface area of cubes = 120 × (6 × side2)
⇒ Total surface area of cubes = 2880
⇒ Percentage increase in the total surface area = (2880 – 592) /592 × 100 = 386.50%
Total surface area of cuboid = 2 × (lb + bh + hl)
⇒ total surface area. = 2 × (8 × 10 + 10 × 12 + 12 × 8) = 592
Let the number of small cubes formed be x
⇒ Volume of cubes = x × (volume of a cube) = 8x
? Volume of cubes = Volume of cuboid
⇒ 8x = 960
⇒ x = 120 (number of cubes formed)
Total surface area of cubes = 120 × (6 × side2)
⇒ Total surface area of cubes = 2880
⇒ Percentage increase in the total surface area = (2880 – 592) /592 × 100 = 386.50%