Question

A wheel 14 m deep is to me in radius find the cost of cementing the inner curved surface area @ rupees 2 per square metre

Answer 1

Question number 3 .....

Answer 2

$\huge\underline\mathtt\pink{SOLUTION:-}$

Correct Question:

• A well 14 metre deep is 2 metre in radius find the cost of cementing the inner curved surface at the rate of rupees 2 per square metre.

AnswEr:

$\large{\underline{\boxed{\mathfrak\green{Cost \: of \: cementing = Rs.351.68 }}}}$

Given:

• Depth of well(h) = 14 m
• Radius of well(r) = 2 m
• Rate of cementing = Rs.2 per m²

Need To find:

• Cost of cementing = ?

$\huge\underline\mathtt\pink{EXPLANATION:-}$

As the inner curved surface is going to be cemented,so we have to find the area of inner curved surface.

As a well is like a cylinder,so we can find CSA of well using the formula of CSA of cylinder.

Now,

$\star\: \: {\boxed{\mathfrak\blue{Curved \: surface \: area = 2 \pi rh }}}$

Putting the values according to given formula:

⇒ CSA of well = 2 × 3.14 × 2 × 14

⇒ CSA of well = 175.84

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Rate of cementing = Rs.2 per m²

We know,

$\star\: \: {\boxed{\mathfrak\pink{Rate \: of \: cementing = Required \: area \times Rate}}}$

Putting the values:-

➜ Cost of cementing = 175.84 × 2

➜ Cost of cementing = Rs.351.68

$\therefore{\underline{\rm{Cost \: of \: cementing = Rs.351.68 }}}$

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