Question

please tell answer it's very much urgent​

Answer 1

Given :- A hall is 12m long , 10m wide and 5 metre high . Its wall and the roof are to be white washed from inside.

To Find :- the total area to be white washed. the cost of white wash at Rs 5.4p / m².

Answer :- length of the hall = 12m , Breadth of the hall = 10m & height of the wall = 5m .

And the hall is to be whitewashed along with roof. So , while whitewashing floor won't be whitewashed .

So the sides that will be whitewashed will be = Area of four walls + Area of roof .

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

=> ar ( 4 walls ) = 2 × 5m ( 12m + 10m )

=> ar ( 4 walls ) = 10m × 22m.

=> ar ( 4 walls ) = 220 m.

Area of roof = lenght × breadth

=> ar ( roof ) = 12 m × 10 m.

=> ar ( roof ) = 120m² .

★Hence total area = 220m² + 120m² = 340m².

Rate of white washing = Rs 5.40/m².

Therefore cost of whitewashing = Rs 5.40/m² × 340m² = Rs 1836.

★Hence the total cost is Rs 1836.