Percentage : Aptitude Test | RRB Group D

  • Percentage
  • 12. 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

Answer: Option 'C'

Let the amount paid to X per week = x
and the amount paid to Y per week = y
Then x + y = 550
But x = 120% of y = 120y/100 = 12y/10 
∴12y/10 + y = 550
⇒ y[12/10 + 1] = 550
⇒ 22y/10 = 550
⇒ 22y = 5500
⇒ y = 5500/22 = 500/2 = Rs.250

  • 13. 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. 19.70
   B.) Rs. 19.2
   C.) Rs. 19.85
   D.) Rs. 18.70

Answer: Option 'A'

Total cost of the items he purchased = Rs.25
Given that out of this Rs.25, 30 Paise is given as tax
=> Total tax incurred = 30 Paise = Rs.30/100
Let the cost of the tax free items = x
Given that tax rate = 6%
∴ (25−30/100−x)6/100 = 30/100
⇒ 6(25 −0.3 −x) = 30
⇒ (25 − 0.3 − x) = 5
⇒ x = 25 − 0.3 − 5 = 19.7

  • 14. The Shopkeeper increased the price of a product by 25% so that customer finds it difficult to purchase the required amount. But somehow the customer managed to purchase only 70% of the required amount. What is the net difference in the expenditure on that product? 
   A.) 10% more
   B.) 5% more
   C.) 12.5% more
   D.) 17.5% more

Answer: Option 'C'

Quantity X Rate = Price
1 x 1 = 1
0.7 x 1.25 = 0.875
Decrease in price = (0.125/1) × 100 = 12.5%

  • 15. In a competitive examination in State A, 6% candidates got selected from the total appeared candidates. State B had an equal number of candidates appeared and 7% candidates got selected with 80 more candidates got selected than A. What was the number of candidates appeared from each State? 
   A.) 8000
   B.) 8200
   C.) 8020
   D.) 7800

Answer: Option 'A'

State A and State B had an equal number of candidates appeared.
In state A, 6% candidates got selected from the total appeared candidates
In state B, 7% candidates got selected from the total appeared candidates
But in State B, 80 more candidates got selected than State A
From these, it is clear that 1% of the total appeared candidates in State B = 80
=> total appeared candidates in State B = 80 x 100 = 8000
=> total appeared candidates in State A = total appeared candidates in State B = 8000

  • 16. Number decreased by 20% gives 480. The number is: 
   A.) 500
   B.) 600
   C.) 550
   D.) None of these

Answer: Option 'B'

Formula = TOTAL=100% ,INCRESE = "+" DECREASE= "-" 
A number means = 100 % 
That same number Decreased by 20 % = 80 % 
80 % ------> 480 (80 × 6 = 480) 
100 % ------> 600 (100 × 6 = 600)

  • 17. If 20% of a certain number is 80, then what is 30% of that number? 
   A.) 100
   B.) 120
   C.) 140
   D.) 150

Answer: Option 'B'

20% = 20 × 4 = 80 
30% = 30 × 4= 120

  • 18. If 40% of a certain number is 120, then what is 90% of that number? 
   A.) 150
   B.) 200
   C.) 240
   D.) 270

Answer: Option 'D'

40% = 40 × 3 = 120 
90% = 90 × 3 = 270

  • 19. When a number is first increased by 10% and then reduced by 10%, The number is: 
   A.) Does not change
   B.) Decreases by 1%
   C.) Increases by 1%
   D.) None of these

Answer: Option 'B'

Farmula = AFTER INCREASED 10% × AFTER REDUCED 10%/TOTAL 100% 
= 110 × 90/100 = 99 % 
= Decreases by 1%

  • 20. The Shopkeeper increased the price of a product by 25% so that customer finds it difficult to purchase the required amount. But somehow the customer managed to purchase only 70% of the required amount. What is the net difference in the expenditure on that product? 
   A.) 10% more
   B.) 5% more
   C.) 12.5% more
   D.) 17.5% more

Answer: Option 'C'

Quantity X Rate = Price
1 x 1 = 1
0.7 x 1.25 = 0.875
Decrease in price = (0.125/1) × 100 = 12.5%