a A class room is 7m long, 6.5m wide and 4m high. It has one door 3m X

1.	a A class room is 7m long, 6.5m wide and 4m high. It has one door 3m X 1.4m and threewindows measuring 2m x 1m. The interior walls are to be painted. Find the cost of painting atthe rate of Rs 3.50 per m2.
Answer» Area of four walls=(2h(l+b)) =(2x4(7+6.5)) =(8x13. 5) =108m square area of one window =3mx1. 4m =4.2m square area of three window =3(2mx1m) =6m square total area of windows =(4.2+6)m square =10.2m square Area for whitewashing =(108-10.2)m square =97.8m square cost of 1 m square white washing = 3.50rupee cost of 97.8m square white washing=3.50x97.8 =342.3 rupees

a A class room is 7m long, 6.5m wide and 4m high. It has one door 3m X 1.4m and threewindows measuring 2m x 1m. The interior walls are to be painted. Find the cost of painting atthe rate of Rs 3.50 per m2.

Answer»

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

=(2x4(7+6.5))

=(8x13. 5)

=108m square

area of one window =3mx1. 4m

=4.2m square

area of three window =3(2mx1m)

=6m square

total area of windows =(4.2+6)m square

=10.2m square

Area for whitewashing =(108-10.2)m square

=97.8m square

cost of 1 m square white washing = 3.50rupee

cost of 97.8m square white washing=3.50x97.8

=342.3 rupees