Question

a classroom is 12m long,7m wide and 4m high.find the cost of repairing the walls and ceiling
,At the rate of Rs 15 per square metre

Answer 1

length=12m
breadth=7m
Height=4m
Total surface area = 2(lb+lh+bh)
= 2((12×7)+(12×4)+(7×4))
=2(84+48+28)
=2(160)
=320m^2
Area of floor=l×b
=12×7
=84

Area to be repaired=320-84
=236m^2

Cost to repair 1m^2=RS 15
Cost to repair 236m^2 = 236×15
= RS 3540

Answer 2

Answer:

$3540 \div 15 = 5$