# Percentage Questions and Answers – Set 4

This set of Aptitude Questions and Answers (MCQs) focuses on “Percentage – Set 4”.

1. The speed of a bus is decreased by 40%. If the distance to be covered is increased by 70% find the percentage change in time taken.
a) 113% increase
b) 118% increase
c) 113.8% increase
d) 183.3% increase

Explanation: Let the speed of the bus be 100 units and the distance be 100 units.
The time taken initially = 100 / 100 = 1 unit
The change in speed = (-) 40% = 100 – 40% of 100 = 100 – 40 = 60 units
The change in distance = (+) 70% = 100 + 70% of 100 = 100 + 70 = 170 units
Time taken now = distance / speed = 170 / 60 units
Change = 170 / 60 – 1 = 170 / 60 – 60 / 60 = 110 / 60
Percentage change = (110 / 60) / (1) * 100 = 11000 / 60 = 183.3% increase

2. The average age of a class of 5 boys increases by 20% if the age of the teacher is taken into consideration. What percentage of teacher’s age is the average age of the boys?
a) 45.45%
b) 56.56%
c) 67.67%
d) 34.34%

Explanation: Let the average age of the class be 100.
The average age of the class after the teacher’s age is added = 100 + 20% of 100 = 100 + 20 = 120
The total age of the 5 boys = 100 * 5 = 500
The total age of the 5 boys including the age of the teacher = 120 * 6 = 720
The age of the teacher = 720 – 500 = 220
The percentage of age of teacher equivalent to average age of the boys:
Let the percentage be x.
X% of 220 = 100
X = 100 / 220 * 100 = 10,000 / 220 = 45.45%

3. A bottle of soft drink contains 750ml of drink. If per sip 20ml of drink is taken out, Find the percentage decrease in the quantity of the drink after 23 such sips.
a) 60.33%
b) 61.33%
c) 60.77%
d) 61.77%

Explanation: The quantity of the drink taken out after 23 sips = 23 * 20 = 460 ml
460ml of 750 ml in percentage = 460 / 750 * 100 = 61.33%

4. A sentence contains 13 words. A paragraph contains 11 such sentences. A page contains 3 such paragraphs. A story contains 20 such pages. What is the percentage of 1440 words in the entire story?
A) 16.78%
b) 17.68%
c) 18.67%
d) 18.76%

Explanation: The total number of words in the story = 13 * 11 * 3 * 20 = 8580 words
1440 words of 8580 words in percentage = 1440 / 8580 * 100 = 16.78%

5. There are 11 balls in a bag of which 6 are blue and 5 are red. A ball is drawn at random, what is the probability, in percentage, that the ball is red in colour?
a) 45.54%
b) 45.45%
c) 54.45%
d) 54.54%

Explanation: The probability that the ball is red in colour is 5 / 11.
To express that in percentage:
5 / 11 * 100 = 500 / 11 = 45.45%

6. Out of 120 students in a class 48 like tennis, 59 like football and 73 like cricket. What is the percentage of maximum possible number of students who like all the three games? It is known that all the students like at least one game.
a) 20%
b) 22%
c) 25%
d) 32%

Explanation: The maximum number of students possible who like all the games = (48 + 59 + 73 – 120) / 2 = 60 / 2 = 30
(The total will be 18 like only tennis, 29 like only football, 43 like only cricket and 30 like all.)
30 / 120 * 100 = 25%

7. If there are 62 keys on my laptop, what is the percentage of the alphabet keys?
a) 41%
b) 42%
c) 43%
d) 44%

Explanation: There are 26 alphabets in total.
The percentage of alphabet keys = 26 / 62 * 100 = 41.93% ≈ 42% keys are alphabet keys.

8. There are 1250 cars in a factory. The factory produces 5 cars hourly. If the sales of the factory are 50 cars per day, what will be the sale percentage to the total cars held by the factory after 5 days. It is known that the factory runs 8 hours daily.
a) 17.2%
b) 17.3%
c) 17.4%
d) 17.5%

Explanation: The total number of cars produced till the end of 5 days:
1250 cars in stock.
Cars produced in 5 days = 5 * 8 * 5 = 200 cars
Cars sold in 5 days = 50 * 5 = 250
Sales to stock percent = 250 / (1250 + 200) * 100 = 250 / 1450 * 100 = 17.24%

9. The total production of a company is increased by 25%. The total sales of a company are increased by 50%. If the company can clear previous stock of 50000 units in 20 days, Find the current production speed of the company (per day). It is known that the previous sales of the company and the previous production of the company were in same ratio.
a) 12,500 units per day
b) 25,000 units per day
c) 15,000 units per day
d) 1,25,000 units per day

Explanation: It is given that the previous sales and the production of the company were in same ratio that means equal.
Let the previous sales and production be x.
The new sales of the company = x + 50% of x = x + .5x = 1.5x
The new production of the company = x + 25% of x = x + .25x = 1.25x
The difference between sales and production of the company = 1.5x – 1.25x = 0.25x
The stock cleared in 20 days = 50,000 units
The stock cleared per day = 50,000 / 20 = 2500 units
0.25x = 2500 units
X = 2500 / 0.25 = 10,000 units
The current production speed = 1.25x = 10,000 * 1.25 = 12,500 units per day.

10. The total sales of a company is 20% of its production. If after 40 days 1,20,000 units of goods are stocked, find the sales of the company per year.
a) 13,76,750 units
b) 13,86,750 units
c) 13,68,750 units
d) 13,67,750 units

Explanation: The stock after 40 days = 1,20,000 units
The stock after a day = 1,20,000 / 40 = 3,000 units
The difference between sales and production:
Sales is 20% of the production.
Let the production be 100.
Sales is 20% of 100 = 20
Difference = 100 – 20 = 80
Difference in percentage = 80 / 100 * 100 = 80%
The stocking speed is 80% of the production.
3,000 units per day is 80% of the production per day.
100% of the production = 3000 / 80 * 100 = 3,750 units per day
Production per year = 3,750 * 365 = 13,68,750 units