Q3 of 20 Page 225

A metal cuboid of dimension 22 cm. × 15 cm. × 7.5 cm. was melted and cast into a cylinder of height 14 cm. What is its radius?

Given, A metal cuboid of dimension 22 cm. × 15 cm. × 7.5 cm. was melted and cast into a cylinder of height 14 cm

According to the question the volume remains same after casting the cuboid inti cylinder, i.e. lbh = πr2h.


22 × 15 × 7.5 = 3.14 × r2 × 14


r2 =


r =


r = 7.5cm


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