Quant Quiz - (Topic► Percentage)

Q1)-In an election between two candidates, one got 55% of the total valid votes, 20% of the votes were invalid. If the total number of votes was 7500, the number of valid votes that the other candidate got, was:

2700

2900

3000

3100

Ans.- A
Number of valid votes = 80% of 7500 = 6000.
Valid votes polled by other candidate = 45% of 6000
= (45/100 x 6000 ) = 2700

Q2)-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?

42, 33

44, 36

43, 36

42, 36

Ans.- A
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) = 56/100(2x+9)
=>(x+9) = 14/25(2x+9)
=> 25x + 225 = 28x + 126
=> 3x = 99
=> x = 33
Then (x + 9) = 33 + 9 = 42
Hence their marks are 33 and 42

Q3)-Number decreased by 20% gives 480. The number is:

500

600

550

None of these

Ans.- 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)

Q4)-In an examination, 34% of the students failed in mathematics and 42% failed in English. If 20% of the students failed in both the subjects, then find the percentage of students who passed in both the subjects.

40%

42%

44%

46%

Ans.- C
Failed in mathematics, n(A) = 34
Failed in English, n(B) = 42
n(A∪B)=n(A)+n(B)−n(A∩B)=34+42−20=56
Failed in either or both subjects are 56
Percentage passed = (100−56)%=44%

Q5)-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?

Rs 15

Rs 12

Rs 19.70

Rs 15.80

Ans.- C
tax = 30 paise = Rs.0.3
tax is 6%.
i.e., Rs.0.3 is 6% of the taxable item.
Therefore, cost of taxable item =(0.3×100)/6=5
cost of the tax free items =25−(0.3+5)=19.7

Q6)-What percent of a day is 6 hours?

6.25 %

20 %

25 %

12.5 %

Ans.- C
Total hours in a day = 24

Q7)-The population of a town increased from 1,75,000 to 2,62,500 in a decade. The average percent increase of population per year is:

4.37%

5%

6%

8.75%

Ans.- B
Increase in 10 years = (262500 - 175000) = 87500.
Increase% =(87500/175000) x 100 % = 50%.
Required average = (50/10) % = 5%.

Q8)-If number x is 10% less than another number y and y is 10% more than 125, then find out the value of x.

123

122

122.25

123.75

Ans.- D
y is 10% more than 125
⇒y=125+12.5=137.5
x is 10% less than y
⇒x=137.5−13.75=123.75

Q9)-Teacher took exam for English, average for the entire class was 80 marks. If we say that 10% of the students scored 95 marks and 20% scored 90 marks then calcualte average marks of the remaining students of the class.

60

70

75

80

Ans.- C
Lets assume that total number of students in class is 100 and required average be x.
Then from the given statement we can calculate :
(10 * 95) + (20 * 90) + (70 * x) = (100 * 80)
=> 70x = 8000 - (950 + 1800) = 5250
=> x = 75.

Q10)-aghu’s salary was decreased by 20% and subsequently increased by 20%, How much percent does he lose?

3 %

2 %

4 %

5 %

Ans.- C
Let Raghu’s original salary = Rs.100
Now salary is = 120% of 20% of 100 = 150 / 100 x 80 / 100 x 100 = 24.
So, Raghu’s Decrease salary is = 4%