Question

A closed metalic cylinder has diameter 56 and hieght 272 cm find the cost of the metal used if its cost 80 rupees per meter square.
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Answer 1

Given :-

Diameter of the cylinder = 56cm

Therefore it's radius = 56/2 (since the radius is half of the length of it's diameter)

= 28cm

Height of the cylinder = 272cm

Since it's a closed cylinder, we've to find it's total surface area TSA to find the total cost.

Formula to find the TSA of a cylinder = 2πr(h + r)

» It's total surface area = 2πr(h + r)

= 2 × 22/7 × 28 (272 + 28)

= 44 × 4

= 176 × 300

= 52800cm²

In m² = 52800/10000 = 5.28m²

Hence, total cost of the metal @ rupees 80 per m² = 5.28 × 80

= Rupees 422.4 final answer

Answer 2

Answer :-

The cost of the metal used is Rs. 422.4 .

Explanation :-

Diameter of closed metallic cylinder = 56 cm

So,

its Radius = r = 56/2 = 28 cm

& Height = h = 272 cm

________________[Given]

• We have to find the cost of metal used .

We know that,

Total surface area of metallic cylinder = 2πr(r + h)

= 2 × 22/7 × 28 × (28 + 272)

= 2 × 22 × 4 × 300

= 44 × 1200

= 52800 cm²

= 5.28 m²

Now,

Cost of making per square meter of metal = Rs.80

So,

Total cost of making the whole metal

= 5.28 × 80

= Rs. 422.4

____________________________

∴ Cost of the metal used is Rs. 422.4

____________________[Answer]