03. Sample questions for Wipro Placements Papers with Solutions - Aptitude Questions Percentages

          Sample questions for Wipro Placement Papers        

Sample questions for Wipro Placement Questions  – Aptitude  Solved Problem 1

Find the percentage saving, in buying a dozen articles for Rs. 126 instead of Rs. 12 for one?
a) 12                    b) 12 1/2                              c) 15                      d) 16 2/3

Answer: B

Explanation:

If bought at Rs 12 for 1 => Cost price of the dozen articles = 12 x 12 =Rs 144

     But given cost of price of the dozen articles = Rs 126

     Savings in Rupees = 144 -126 = 18

         % Savings = $\frac{18}{144}$  x 100% =12 ½%

Sample questions for Wipro Placement Papers with Solutions – Aptitude Question 2

Ravi's salary was reduced by 25%.Percentage increase to be effected to bring the salary to the original level is
a) 20%                   b) 25%                             c) 33  1/3 %                       d) 30%
Answer: C
Explanation:
Let Ravi’s initial salary be Rs 100.
After reduction of  25% , Ravi’s salary  becomes Rs 75.
To bring his salary back, the salary must be increased by Rs 25
Percentage increase required = $\frac{Increase}{Value}$ x 100%

    =  $\frac{25}{75}$ x 100% = 100/3 % = 33 1/3%

Sample questions for Placement Questions with Answers – Percentages Solved Problem 3

Salary of Suresh is 25% less than the salary of Ramesh. By how much percent the salary of Ramesh is more than the salary of Suresh?
a)12 1/2%              b)16 2/3%               c)33 1/3%               d) 26 2/3%

Answer: D

Explanation:

Let salary of Ramesh be Rs 100

As Suresh’s salary is 25% less than the salary of Ramesh

=> Suresh’s salary= Rs 75
              Ramesh’s Salary is Rs 25 more than the salary of Suresh.

   Required Percentage =  $\frac{Difference}{Suresh's Salary}$ x 100%
                               = $\frac{25}{75}$ x 100% = 33 1/3%

         

Sample questions for Placement Questions with Explanations–Aptitude Percentages Problem 4

On increasing the price of T.V. sets by 30%, their sale decreases by 20%. What is the effect on the revenue receipts of the shop ?
a) 4% increase                  b) 4% decrease      c) 8% increase          d) 8% decrease
Answer:  A
Explanation:
Let the price of TV  be = Rs.100, and number of units sold = 100
Then, Revenue receipts = Rs.(100 × 100) = Rs.10000

Now price is increased by 30% and sales are decreased by 20%.

Now price of TV is Rs 130 and number of sales is 80
New Revenue receipts = Rs.(130 × 80) = Rs.10400
Percentage Increase % = Increase/Initial Value × 100

                                  =   $\frac{400}{10000}$ x 100 % = 4% increase

Direct Formula :

A price is increased by a% and sales are decreased by b%, then overall percentage change in its revenue = a – b - $\frac{ab}{100}$ %

        Therefore, % change in receipts = 30 -20 – $\frac{30 \times 20}{100}$ %

                                                    = 4% increase

Sample questions for Placement Questions  – Aptitude Questions Percentages Question 6

The Maruti price has risen by 25% and the sales have come down by 4%. What is the total percentage change in revenue?

a)20%                              b)30%                    c)35%                     d)38%

Answer: A

Explanation:
Let the price of TV  be = Rs.100, and sales = 100 units
Then, Revenue receipts = Rs.(100 × 100) = Rs.10000

Now price is increased by 25% and sales came down by 4%.

Now price of Maruti is Rs 125 and number of sales is 96
New Revenue receipts = Rs.(125 × 96) = Rs.12000
Percentage Increase % =  Increase/Initial Value × 100

                                  =   $\frac{2000}{10000}$ x 100 % = 20%

Direct Formula:

A price is increased by a% and sales are decreased by b%, then overall percentage change in its revenue = a – b - ab/100  %

        Therefore ,% change in receipts = 25 -4 – $\frac{25 x 4 }{100}$ %

                                                  = 20%

Sample questions for Previous Placement Papers with Solutions - Percentages Problem 6

Water tax is increased by 20% but its consumption is decreased by 20%. Then, the increase or decrease in the expenditure of the money is:
a) No change           b) 5% decrease        c) 4% increase      d) 4% decrease
Answer: d
Explanation:
Let water tax is Rs 100 per liter and price of each liter is Rs 100

Expenditure = Tax x Consumption = 100 x 100 = Rs 10000

Now Water tax is increased by 20% and consumption is decrease by 20%.

There now tax is Rs 120 per litre and consumption is 80 liters

Expenditure after changes = 120 x 80 = Rs 9600

  % Decrease in expenditure = Decrease/Initial Expenditure x 100%

                                        = 400/10000 x 100 % = 4% decrease

Direct Formula:

A tax is increased by a% and consumption is decreased by a%, then overall percentage change in its revenue = - (a²/100)%

       Therefore ,% change in expenditure  = -(20²/100)%                                                                                                               =- 4%

                                                          = 4% decrease
           

Sample questions for Placement Papers with Answers – Aptitude Percentages Question 7

If radius of a circle is diminished by 10%, then its area is diminished by
a) 10%                   b) 19%                   c) 20%                   d) 36%

Answer: d
Explanation: Let initial radius is 10 cm

            Then, Area of the circle = pi x R X R

                                                    =3.14 x 10 x 10 =pi x R X R

                                                    =3.14 x 10 x 10 =314

Now the radius is decreased by 10%, now the radius is 90% of 10= 9

  Now , Area of the circle = pi x R X R

                                         =3.14 x 10 x 10 =pi x R X R

                                         =3.14 x 9 x 9  =254.34

    Area diminished by =314-254.34/314 x 100% = 19% decrease in area.

Shortcut :

 As radius is decreased by 10%, while calculating the area , we take radius twice. So decrease happens 2 times .

The formula is = -10-10 + 10 x 10/100

                    = -19% = 19% decrease in area.

Sample questions for Placement Papers with Answers – Sample questions for Aptitude Question Percentage 8

If the price of petrol increases by 25% and Kevin intends to spend only 15% more on petrol. By how much percent should he reduces the quantity of petrol that he buys?

a)5%                               b)8%                      c)10%                     d)15%

Answer: B
Explanation: Let initial price of petrol is Rs 10 and his consumption is 10 litres.

        So his previous spending on petrol = 10 x 10 = Rs 100
  Now Petrol Price is increased by 25% = Price after increase is Rs 12.50

Now Kevin ready to spend only 15% more on petrol =>So he increases the expenditure by 15%.

Now his spending on petrol becomes Rs 115.
Now his consumption in litres = 115/12.5 =9.2 litres

        Percentage reduction in his consumption = 10- 9.2/10   x 100 = 8%

So the quantity is reduced by 8%

Sample questions for Placement Papers  Aptitude Questions –Percentages Question 9

In an examination, 35% of total students failed in Hindi, 45% failed in English and 20% in both. The percentage of these who passed in both the subjects is:
a) 10%                   b) 20%                             c) 30%                             d) 40%
Answer: D
Explanation: Failed in Hindi n(a)= 35%    Failed in English n(B)= 45%

                Failed in both subjects n(a∩b) = 20 %
We know that  n(a∪b) = n(a) + n(b) − n(a∩b)
Failed in Hindi or English = 35 + 45 – 20 = 60
Students who passed in both subjects = 100 – 60 = 40. 

Sample questions for previous placement papers with answers – Percentages Question 10

If there are 5,000 voters out of which 20% are not eligible to vote and there are two candidates contesting. The winning candidate won by 15% of votes. What is the total number of votes he got?

a)2300                             b)2500          c)3000                    d)2700

Answer: A

Explanation: 20% of the votes are not eligible to vote
So Number of voters eligible for voting = 5000 ×  80/100= 4000

 Difference between votes got by winner and looser = 15%

Number of votes extra got by the winning candidate = 4000 × 0.15 = 600

Remaining votes are 4000-600= 3400

Each one got = 3400/2 = 1700

Now winner got = 1700 + 600 = 2300

Sample questions for Placement Papers Previous Questions–Aptitude Question Percentages 11

The population of a town increases 4% annually but is decreased by emigration annually to the extent of (1/2)%. What will be the increase percent in 3 years?
a) 9.8                     b) 10                               c) 10.5                             d) 10.8

Answer: d
Explanation: Overall increase in population is 4% - (1/2)% = 3 ½% =7/2%

  Let initial population of town be 1000.

After 3 years, the population will be => 1000 x $\frac{207}{100}$ x $\frac{207}{100}$ x $\frac{207}{100}$

                                                =>1108.72

  % increase in 3 years = 1108.72-1000/1000 x 100% = 10.8 (approximately)

Sample questions for Placement Papers with Explanations–Aptitude Questions Percentages 12

In a certain school, 20% of the students are below 8 yrs of age. The number of students above 8 yrs of age is (2/3) of the number of students of 8 years age which is 96. What is the total number of students in the school?

a)120                               b)150                                c)180                     d)200
Answer: D

Explanation: Let total number of students be N

Below 8 years of age are 25% of N = 0.25N
⇒ 0.2x + $\frac{2}{3}$
 × 96 + 96 = N
       Therefore total number of students N = 200