Question

find the cost of painting a cuboid
of dimension 15cm x 10cm x 8cm at
the rate of 5 paisa per square
centimetes​

Answer 1

Given :-

• Length = 15 cm
• Breadth = 10 cm
• Height = 8 cm
• 1 cm² painting = 5 paise

To find :-

Cost of painting cuboid = ?

Formula used:

→ TSA of cuboid = 2(lb + bh + hl)

Here, we have taken TSA or total surface area because the whole cuboid is to be painted.

Solution :-

TSA of cuboid = 2(lb + bh + hl)

➥ TSA = 2((15 × 10) + (10 × 8) + (8 × 15))

➟ TSA = 2(150 + 80 + 120)

➜ TSA = 2(350)

➝ TSA = 700 cm²

Now, for finding the cost;

1 cm² = 5 paise

700 cm²

= 700 × 5

= 3500 paise

= ₹ 35

∴ The cost of painting = ₹ 35

Answer 2

Given :

• Length of Cuboid = 15cm
• Breadth of Cuboid = 10cm
• Height of Cuboid = 8cm
• Rate of Painting = 5paisa per cm

To Find :

• Total Cost of Painting the Cuboid

Solution :

➞ TSA of cuboid = 2(lb + bh + hl)

➞ TSA = 2(15 × 10 + 10 × 8 + 8 × 15)

➞ TSA = 2(150 + 80 + 120)

➞ TSA = 2 × 350

➞ TSA of Cuboid = 700 cm²

⠀⠀⠀⠀⠀⠀⠀⠀________________

Now,

⟾ Cost of 1cm² of painting = 5 paisa

⟾ Cost of 700cm² of painting = 5 × 700

⟾ Cost of 700cm² of painting = 3500paisa

⠀⠀⠀⠀⠀⠀⠀⠀________________

Thus Total Cost of Painting is 3500paisa or ₹35

________________