Given:Perimeter=250m⇒Area of 4 walls =2lh+2bh=2(b+l)h⇒Perimeter of floor of wall =2l+2b⇒2(l+b)=250 m∴ Area of 4 walls =2(l+b)h=250h m2⇒Cost of painting per m2 area = Rs. 10⇒Cost of painting 250h m2 area = Rs(250h×10)= Rs.2500h⇒Painting cost of walls = Rs. 15000⇒2500h=15000⇒h=250015000​⇒h=6m