Aptitude - Percentage

Answer: Option C

Explanation:

20% of a = b	20	a = b.
	100

b% of 20 =		b	x 20		=		20	a x	1	x 20		=	4	a = 4% of a.
		100					100		100				100

Answer: Option D

Explanation:

Let the number of students be x. Then,

Number of students above 8 years of age = (100 - 20)% of x = 80% of x.

80% of x = 48 +	2	of 48
	3

	80	x = 80
	100

x = 100.

Answer: Option B

Explanation:

5% of A + 4% of B =	2	(6% of A + 8% of B)
	3

	5	A +	4	B	=	2		6	A +	8	B
	100		100			3		100		100

	1	A +	1	B	=	1	A +	4	B
	20		25			25		75

		1	-	1	A =		4	-	1	B
		20		25			75		25

	1	A =	1	B
	100		75

A	=	100	=	4	.
B		75		3

Required ratio = 4 : 3

Answer: Option A

Explanation:

Let the number be x.

Then, error =	5	x -	3	x =	16	x.
	3		5		15

Error% =		16x	x	3	x 100	% = 64%.
		15		5x

Answer: Option A

Explanation:

Number of valid votes = 80% of 7500 = 6000.

Valid votes polled by other candidate = 45% of 6000

=		45	x 6000		= 2700.
		100