Question

10 cylindrical pillars of a building have to be
painted. If the diameter of each pillar is 50
cm and
the height is 4 m, what will be the cost of
painting @14 per m*??


​

Answer 1

$\large\underline{\red{\sf \blue{\bigstar} .}}$Given :-

⠀⠀⠀⠀⠀⠀⠀

• 10 cylindrical pillars of a building have to be painted. If the diameter of each pillar is 50 cm and the height is 4 m

⠀⠀⠀⠀⠀⠀⠀

$\large\underline{\red{\sf \green{\bigstar} .}}$To find :-

⠀⠀⠀⠀⠀⠀⠀

• What will be the cost of painting @ 14 per m²

⠀⠀⠀⠀⠀⠀⠀

$\large\underline{\red{\sf \pink{\bigstar} .}}$Solution :-

⠀⠀⠀⠀⠀⠀⠀

• Diameter of cylindrical pillars = 50cm

⠀⠀⠀⠀⠀⠀⠀

• Radius of cylindrical pillars = 50/2 = 25cm = 25/100 = 0.25m

⠀⠀⠀⠀⠀⠀⠀

• Height of cylindrical pillars = 4 m

⠀⠀⠀⠀⠀⠀⠀

• Now, curved surface area of cylindrical pillars

⠀⠀⠀⠀⠀⠀⠀

$\large\underline{\red{\sf \blue{\bigstar} .}}$→ 2πrh

⠀⠀⠀⠀⠀⠀⠀

⠀⠀⠀⠀⠀⠀⠀

Where " r " is radius and " h " is height.

⠀⠀⠀⠀⠀⠀⠀

• → 2 × 22/7 × 0.25 × 4

⠀⠀⠀⠀⠀⠀⠀

• → 44/7 × 1

⠀⠀⠀⠀⠀⠀⠀

• → 44/7 m²

⠀⠀⠀⠀⠀⠀⠀

⠀⠀⠀⠀⠀⠀⠀

$\large\underline{\red{\sf \green{\bigstar} .}}$Area of 10 cylindrical pillars

⠀⠀⠀⠀⠀⠀⠀

• 10 × 44/7 = 440/7 m²

⠀⠀⠀⠀⠀⠀⠀

• The cost of painting @ 14 per m²

⠀⠀⠀⠀⠀⠀⠀

• → Total cost

⠀⠀⠀⠀⠀⠀⠀

• → 440/7 × 14

⠀⠀⠀⠀⠀⠀⠀

• → 440 × 2

⠀

⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀

$\large\underline{\red{\sf \purple{\bigstar} .}}$→ Rs.880

⠀⠀⠀⠀⠀⠀⠀

⠀⠀⠀⠀⠀⠀⠀

$\large\underline{\red{\sf \blue{\bigstar} .}}$Hence,

⠀⠀⠀⠀⠀⠀⠀

⠀⠀⠀⠀⠀⠀⠀

$\large\underline{\green{\sf \red{\bigstar} .}}$Total cost for painting 10 cylindrical pillars is Rs.880

⠀⠀⠀⠀⠀⠀⠀

⠀⠀⠀⠀⠀⠀⠀

⠀⠀⠀⠀⠀⠀⠀

Answer 2

Answer:

$\huge\mathcal\blue{Required \: Answer}$

☃️Given:-

✯10 cylindrical pillars of a building have to be painted. If the diameter of each pillar is 50 cm and the height is 4 m.

☃️To find:-

✯What will be the cost of painting 14 per m².

☃️ Solution:-

↝Diameter of cylindrical pillars = 50cm

⠀⠀⠀⠀⠀⠀⠀

↝Radius of cylindrical pillars = 50/2 = 25cm = 25/100 = 0.25m

⠀⠀⠀⠀⠀⠀⠀

↝Height of cylindrical pillars = 4 m

⠀⠀⠀⠀⠀⠀⠀

Now, curved surface area of cylindrical pillars is 2πrh.

Where " r " is radius and " h " is height.

⠀⠀⠀⠀⠀⠀⠀

→ 2 × 22/7 × 0.25 × 4

⠀⠀⠀⠀⠀⠀⠀

→ 44/7 × 1

⠀⠀⠀⠀⠀⠀⠀

→ 44/7 m²

⠀⠀⠀⠀⠀⠀⠀

Area of 10 cylindrical pillars

⠀⠀⠀⠀⠀⠀⠀

10 × 44/7 = 440/7 m²

⠀⠀⠀⠀⠀⠀⠀

The cost of painting @ 14 per m²

⠀⠀⠀⠀⠀⠀⠀

→ Total cost

⠀⠀⠀⠀⠀⠀⠀

→ 440/7 × 14

⠀⠀⠀⠀⠀⠀⠀

→ 440 × 2

→ Rs.880

⠀⠀⠀⠀⠀⠀⠀

Hence,

Total cost for painting 10 cylindrical pillars is Rs.880.

⠀⠀⠀⠀⠀⠀⠀