Question

The floor of a rectangular hall has a perimeter 250 m. If the cost of painting the four
walls at the rate of 10 per m^2is *15000, find the height of the hall,
[Hint: Area of the four walls =Lateral surface area.]​

Answer 1

Answer:

6m

Step-by-step explanation:

Area= Total cost

Cost per square metre

=15000

10

=1500square metre

Area= L.S.A.

1500 =2h(l+b)

1500=2(l+b)*h

1500=250*h

h=1500

250

h=6m

Answer 2

$\huge\underline\mathrm{SOLUTION:-}$

Let length, breadth, and height of the rectangular hall be l, b, and h respectively.

Area of four walls = 2lh + 2 bh

= 2 (l + b) h

Perimeter of the floor of hall = 2(l + b)

= 250 m

Area of four walls = 2(l + b) h = 250h m2

Cost of painting per square meter area = Rs.10

Cost of painting 250h square meter area = Rs (250 h x 10) = Rs.2500h

However, it is given that the cost of paining the walls is Rs. 15000.

15000 = 2500h

Or h = 6

Therefore:

• The height of the hall is 6 m.

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