Question

Biswas made a box 20 cm long., 15 cm broad and 10 cm high but without a lid. How much cardboard did he use for it?

Answer 1

1000 cm² the answer
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Answer 2

HERE length(l)=20 cm
Breadth(b)=15 cm
Height(h)=10cm
CARDBOARD use=area of four walls+area of base
⇒2(l+b)h+lb
⇒2(20+15)10+20×15
⇒2×35×10 +300
⇒700+300
⇒1000 cm²