Question

Please answer the question number 6 with solution.

Answer 1

Answer:

The height of the wall is 5 meters.

Step-by-step explanation:

given

length = l = 9 m

breadth = b = 7 m

let height be h

So total surface area of 4 walls = 2(lh + bh)

= 2h(9+7)

=32 h m²

Also there is a door whose surface area

= 1.5 x 1 = 1.5 m²

Hence net surface area of wall =

(32h - 1.5)

since cost of painting the walls per sq meter is 50 rs and the total cost is rs 7925, hence

(32h-1.5) x 50 = 7925

=> 32h - 1.5 = 158.5

=> 32 h = 160

=> h = 160/32 = 5 m

Hence the height of the wall is 5 meters.

Answer 2

Answer:

5 m

Step-by-step explanation:

Assuming there are four walls in a room, we have one wall is 9m and another wall is 7 m. We do not know the height.

Area will be 9 h x 2 and 7 h x 2

So it will be 18 h + 14 h = 32 h sq m

Now the door is 1.5 m x 1 m = 1.5 sq m

Now 50 Rs for the cost of painting the walls per sq m

Therefore for Rs 7925 it will be 7925 / 50 = 158.5 sq m

Now total size of the room will be 158.5 + 1.5 = 160 sq m

 Thus 32 h = 160

 h = 160 / 32

h = 5 m

The height of the room is 5 m.