Question

a classroom is 8m long 7 M broad and 4.5 m high. Doors and windows occupy an area of 18 m square .find the cost of whitewashing the walls at the rate of rupees 2.50 per square metre

Answer 1

= 8+7+4.5+18m sq. =27.5
= 27.5/2.5 = 11

Answer 2

HELLO MATE

TSA of room = 2(lb+bh+hl) = 2(32+31.5+36) = 2×99.5. = 199cm square

Subtract 18cm square of doors and windows
199- 18 = 181cm square

Cost = 2.50×181 =452.5

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