Question

A shopkeeper has one laddoo of radius 5 cm. With the same material, how many laddoos of radius 2.5 cm can be made?

Answer 1

Volume of laddoo having radius = 5 cm 

i.e Volume `(V_1) = 4/3 πr^3`

`V_1 = 4/3 xx 22/7 xx (5)^3`

`V_1 = 11000/21 cm^3`

Also volume of laddoo having radius = 2.5 cm

i.e, `V_2 = 4/3 πr^3`

`V_2 = 4/3 xx 22/7 × (2.5)^3`

`V_2 = 1375/21 cm^3`

∴ No of laddoos = `V_1/V_2 = 11000/1375` = 8