Question

A swimming pool is 20 m long, 15 m broad, and 4 m deep. Find the cost of cementing its floor and the walls at the rate of ₹12 per square metre,
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Answer 1

$\huge\underbrace\mathrm\purple{Answer}$

Given details are,

Dimensions of swimming pool are = 20m × 15m ×3m

Where, Length = 20m , Breadth = 15m , Height = 3m

We know,

Area of floor = length × breadth

= 20 × 15

= 300 m²

Area of walls of swimming pool = 2 (lh + bh) cm²

= 2 (20×3 + 15×3)

= 2 (60 + 45)

= 2 (105)

= 210m²

Sum of areas of floor and four walls = area of floor + area of walls

= 300 + 210

= 510 m²

Given, Cost for repairing 1m² area = Rs 25

∴ Cost for repairing 510 m²= 510 × 25

= Rs 12750

$\huge\underbrace\mathrm\red{The\: End}$

Answer 2

$\large\underline{ \underline{ \sf \maltese{ \: Question:- }}}$

• A swimming pool is 20 m long, 15 m broad, and 4 m deep. Find the cost of cementing its floor and the walls at the rate of ₹12 per square metre.

$\large\underline{ \underline{ \sf \maltese{ \: Given:- }}}$

• Length of pool = $\blue{\fbox\orange{20m }}$
• Breadth of pool =$\blue{\fbox\orange{15m }}$
• Height of pool = $\blue{\fbox\orange{4m }}$
• Cost of Cementing 1 ${m}^{2}$ = $\blue{\fbox\orange{₹12 }}$

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$\large\underline{ \underline{ \sf \maltese{ \: Solution:- }}}$

Ar. of pool to be cemented = Ar. of 4 walls + Ar. of floor

$\qquad \quad {:}\longrightarrow \sf{\sf{2( \: l \: + \: b) \: \times \: h \: + \: l \: \times \: b }}$

$\qquad \quad {:} \longrightarrow\sf{\sf{2( \: 20 \: + \: 15) \: \times \: 4 \: + \: 20 \: \times \: 15 }}$

$\qquad \quad {:}\longrightarrow \sf{\sf{ 8 \times \: 35 \: + \: 300 }}$

$\qquad \quad {:}\longrightarrow \sf{\sf{ (\: 280 \: + \: 300 \: ) }}$

$\qquad\quad {:} \longrightarrow \underline \red{\boxed{\sf{ = 580 {m}^{2} }}}$

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Cost of Cementing 1${m}^{2}$= $\blue{\fbox\blue{₹12 }}$

Cost of Cementing 580 ${m}^{2}$ = $\blue{\fbox\purple{12 × 580 }}$

$\begin{gathered}\begin{gathered}\qquad \therefore\: \sf{ Cost\:of \: Cementing= \underline {\underline{ ₹6960 }}}\\\end{gathered}\end{gathered}$

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