The radius of a cylindrical milk container is half its height

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The radius of a cylindrical milk container is half its height and surface area of the inner part is 616 sq. cm. The amount of milk that the container can hold, approximately, is
[Use : √5 = 2.23 and π = 22/7]

Surface area of milk pot. = 2πrh + πr² = πr(2h + r)

=	πh		2h +	h		=	5πrh²	cu.cm.
	2			2			4

∴	5	×	22	× h² = 616
	4		7

⇒ h² =	616 × 4 × 7	=	28 × 28
	5 × 22		5

∴ Volume of milk = πr²h

=	22	×	h²	× h
	7		4

=	22	×	28 × 28 × 28	× h
	28		5 × √5

=	22 × 28 × 28 × √5	×	22 × 28 × 28 × 2.23	× h
	25		25

= 1538.5 cu. cm.
= 1.54 litres
= 1.53 litres (Approx.)