Question

Rishi got two halls in his house painted. It cost him rs 6000 and 6100 respectively to paint the 4 walls of his 2 square halls,of the same height. If the length of one hall exceeds the length of the other by 1m and the cost of painting is rs 5 per square. M. What is the height of the two halls

Answer 1

the length exceeds by 1 meter so the extra is 1×h where h is the height of these walls
so here h×1 = 100
h = 100 meters

Answer 2

The height of the two halls = 5 m

Let the length smaller hall = l

The length of larger hall = l+1

Let the height of both halls = h

Area of 4 walls smaller hall = 4 l×h

Money spent = Rs. 6000

Money spent on painting the walls = area × money per unit area

=> 4 l × h × 5 = 6000

=> 4 l × h = Rs. 1200

=> 4 h= 1200/l

Area of 4 walls of larger hall = 4(l+1)×h

Money spent on painting the walls = 4(l+1) × h ×5 = Rs. 6100

=> 4h= 1220/(l+1)

Equating the two values of 4h -

=> 1200/l = 1220/(l+1)

=> 1200 l + 1200 = 1220 l

=> 20l = 1200

=> l = 60 m

For finding height -

4l×h×5= 6000

=> h = 1200/240

=> h = 5 m

The height of both halls = 5 m

The length of larger hall = 61 m

The length of smaller hall = 60 m