Question

A swimming pool is 25m long , 20m wide, and 2m deep. Find the cost of cementing its floor and four walls at the rate of rupees 20 per m².​

Answer 1

Answer:

Length of pool = 25m

Breadth of pool = 20m

Height of pool=2m

Area to be cemented=2(bh + hl) +lb

=2(20*2+25*2) +25*20

=2(40+50) +500

=2*90+500

=180+500

=680 metres²

Cost of cementing 1 m²= ₹20

Cost of cementing 680 m²=₹20*680=₹1360

Answer 2

Given :

• Length of the swimming pool = 25 m
• Breadth of the swimming pool = 20 m
• Height of the swimming pool = 2 m

To find :

• Cost of cementing its floor

Solution :

Firstly, we will find the area of the four wall and then its cost and then we will find the area of the floor and the cost of cementing it.

Then we will add both the cost to find the combined cost of cementing the four walls and the floor.

Area of four wall = 2(l + b)h

where,

• l = length of the floor
• b = breadth of the floor
• h = height of the floor

Substituting the given values,

⇒ Area = 2(25 + 20) × 2

⇒ Area = 2(45) × 2

⇒ Area = 90 × 2

⇒ Area = 180

Area of the four wall = 180 m²

Cost of cementing the four wall = 180 × 20 = Rs. 3,600

Area of floor = l × b

where,

• l = length of the floor
• b = breadth of the floor

Substituting the given values,

⇒ Area = 25 × 20

⇒ Area = 500

Area of the floor = 500 m²

Cost of cementing the floor = 500 × 20 = Rs. 10,000

Total Cost = Cost of cementing the four wall + Cost of cementing the floor

⇒ Total cost = 10,000 + 3,600

⇒ Total cost = 13,600

Total Cost of cementing the four walls and the floor = Rs. 13,600