Question

The floor of a rectangular hall has a perimeter 250 m. If the cost of painting the four
walls at the rate of Rs 10 per m' is Rs 15000, find the height of the hall.
[Hint: Area of the four walls =Lateral surface area.]​

Answer 1

Answer:

Height of the hall is 6 metres

Step-by-step explanation:

Given:

Perimeter of the floor of hall = 250 m

=> 2(l + b) = 250

Area of four walls = Lateral Surface Area

= 2(l + b)h

= 250h

Cost of painting per m² = Rs. 10

=> Cost of painting 250h m² = 250h × 10

= Rs. 2,500h

2,500h = 15,000

=> h = 15,000/2,500

=> h = 6 m

Hope this helps!

Answer 2

Given:-

• Perimeter of Rectangle = 250m

• Cost of Painting the four walls Per m = Rs.10

• Total Cost of Painting = Rs15000

To Find:-

• The Height of the hall

Formulae used:-

• Lateral Surface area = 2 ( l + b )h

• Perimeter of Rectangle = 2 ( l + b )

Where,

• l = Length
• b = Breadth
• h = Height

Now,

→ Area of four walls = $\rm{\dfrac{Total\:Cost}{Cost\:Per\:m}}$

→ Area of four walls = $\rm{\dfrac{15000}{10}}$

→ Area of four wall = 1500m²

Therefore,

→ Area of four wall = Lateral Surface area

→ 1500 = 2 ( l + b )h

But Perimeter is given

So,

→ Perimeter = 2 ( l + b )

→ 250 = 2 ( l + b )

Now,

→ 1500 = 2 ( l + b ) h

→ 1500 = 250h

→ h = 1500/250

→ h = 6

Hence, The Height of floor is 6m.