Mathematics for SSC & Bank Po/Clerk Exam

Percentage 1. Two students appeared at an examination. One of them secured 9 marks more than the other and his marks was 56% of the sum of their marks. What are the marks obtained by them?
A. 42, 33	B. 42, 36
C. 44, 33	D. 44, 36

2. If A = x% of y and B = y% of x, then which of the following is true?
A. None of these	B. A is smaller than B.
C. Relationship between A and B cannot be determined.	D. If x is smaller than y, then A is greater than B.
E. A is greater than B.

3. If 20% of a = b, then b% of 20 is the same as:
A. None of these	B. 10% of a
C. 4% of a	D. 20% of a

4. Two numbers A and B are such that the sum of 5% of A and 4% of B is two-third of the sum of 6% of A and 8% of B. Find the ratio of A : B.
A. 2 : 1	B. 1 : 2
C. 1 : 1	D. 4 : 3

5. Two employees X and Y are paid a total of Rs. 550 per week by their employer. If X is paid 120 percent of the sum paid to Y, how much is Y paid per week?
A. Rs. 150	B. Rs. 300
C. Rs. 250	D. Rs. 200

6. Rahul went to a shop and bought things worth Rs. 25, out of which 30 Paise went on sales tax on taxable purchases. If the tax rate was 6%, then what was the cost of the tax free items?
A. Rs. 15	B. Rs. 12.10
C. Rs. 19.70	D. Rs. 16.80

7. The population of a town increased from 1,75,000 to 2,62,500 in a decade. What is the average percent increase of population per year?
A. 4%	B. 6%
C. 5%	D. 50%

8. Three candidates contested an election and received 1136, 7636 and 11628 votes respectively. What percentage of the total votes did the winning candidate get?
A. 57%	B. 50%
C. 52%	D. 60%

9. A fruit seller had some oranges. He sells 40% oranges and still has 420 oranges. How many oranges he had originally?
A. 420	B. 700
C. 220	D. 400

10. A batsman scored 110 runs which included 3 boundaries and 8 sixes. What percent of his total score did he make by running between the wickets?
A. 45411 %	B. 45 %
C. 45511 %	D. 44511 %

Answer

1. Option A

Explanation :

Let the marks secured by them be x and (x + 9)

Then sum of their marks = x + (x + 9) = 2x + 9

Given that (x + 9) was 56% of the sum of their marks

=>(x+9)=56100(2x+9)=>(x+9)=1425(2x+9)

=> 25x + 225 = 28x + 126


=> 3x = 99


=> x = 33


Then (x + 9) = 33 + 9 = 42


Hence their marks are 33 and 42

2. Option A

Explanation :

A = x100y=xy100.................(Equation 1)B = y100x=yx100.................(Equation 2)

From these equations, it is clear that A = B

3. Option C

Explanation :

20% of a = b

=> b = 20100ab% of 20 = b10020=(20100a)10020=20×20×a100×100=4a100 = 4% of a

4. D

5. C

6. C

7. C

8. A

9. B

10. C

But x = 120% of y = 120y100=12y10∴12y10+y=550⇒y[1210+1]=550⇒22y10=550⇒22y=5500⇒y=550022=5002

5% of A + 4% of B = 23(6% of A + 8% of B)5A100+4B100=23(6A100+8B100)⇒5A+4B=23(6A+8B)⇒15A+12B=12A+16B⇒3A=4B⇒AB=43⇒A:B=4:3

5% of A + 4% of B = 23(6% of A + 8% of B)5A100+4B100=23(6A100+8B100)⇒5A+4B=23(6A+8B)⇒15A+12B=12A+16B⇒3A=4B⇒AB=43⇒A:B=4:3