Diameter of a rain drop = 6 mm
Radius of a rain drop = 6/2 mm
= 3 mm
Volume of a rain drop = (4/3) × pi × r^3
= (4/3) × (22/7) × 3 × 3 × 3 mm^3
= (4 × 22)/7 × 3 × 3 mm^3
= (88/7) × 9 mm^3
= 792/7 mm^3
= (792/7)/1000 ml
= 792/7000 ml
= 99/875 ml
No. of raindrops reqd. = Vol. of cylindrical can / vol. of a rain drop
= 355/(99/875)
= (355×875)/99
= 310625/99
= 3137.62
Therefore 3137.62 rain drops are reqd.
