Percentage MCQs With Explanation-Sainik School Math Study Material Notes free pdf download
o calculate percentage, you can use the following formula:
percentage = (part / whole) * 100
where:
part
is the value you want to find the percentage ofwhole
is the total value
For example, if you want to find the percentage of 20 out of 100, you would use the following formula:
percentage = (20 / 100) * 100 = 20%
This means that 20 is 20% of 100.
You can also use a calculator to calculate percentage. Most calculators have a percentage button that you can use to calculate percentage directly.
Here are some more examples of how to calculate percentage:
- What is the percentage of 50 out of 200?
percentage = (50 / 200) * 100 = 25%
- What is the percentage of 75 out of 150?
percentage = (75 / 150) * 100 = 50%
- What is the percentage of 100 out of 1000?
percentage = (100 / 1000) * 100 = 10%
Question 1: What is 20% of 100?
Answer: 20% of 100 is 20. To calculate this, we can use the following formula:
percentage of a number = (percentage / 100) * number
So, in this case, we have:
20% of 100 = (20 / 100) * 100 = 20
Question 2: What is 50% of 50?
Answer: 50% of 50 is 25. We can use the same formula from the previous question to calculate this:
50% of 50 = (50 / 100) * 50 = 25
Question 3: What is 100% of 25?
Answer: 100% of 25 is 25. This is because 100% means “all of”, so 100% of 25 is simply 25.
Question 4: What is the percentage of boys in a class with 26 boys and 24 girls?
Answer: To calculate this, we need to divide the number of boys by the total number of students and multiply by 100:
percentage of boys = (number of boys / total number of students) * 100
So, in this case, we have:
percentage of boys = (26 / 50) * 100 = 52%
Question 5: What is the percentage increase from 10 to 20?
Answer: To calculate the percentage increase, we need to divide the difference between the two numbers by the original number and multiply by 100:
percentage increase = (difference between new and old numbers / old number) * 100
So, in this case, we have:
percentage increase = (20 - 10) / 10 * 100 = 100%
Question 6: What is 33% of 120?
Answer: 33% of 120 is 39.6. We can use the same formula from the previous questions to calculate this:
33% of 120 = (33 / 100) * 120 = 39.6
Question 7: What is 75% of 80?
Answer: 75% of 80 is 60. We can use the same formula from the previous questions to calculate this:
75% of 80 = (75 / 100) * 80 = 60
Question 8: What is the percentage of girls in a class with 32 girls and 28 boys?
Answer: To calculate this, we need to divide the number of girls by the total number of students and multiply by 100:
percentage of girls = (number of girls / total number of students) * 100
So, in this case, we have:
percentage of girls = (32 / 60) * 100 = 53.33%
Question 9: What is the percentage decrease from 30 to 20?
Answer: To calculate the percentage decrease, we need to divide the difference between the two numbers by the original number and multiply by 100:
percentage decrease = (difference between old and new numbers / old number) * 100
So, in this case, we have:
percentage decrease = (30 - 20) / 30 * 100 = 33.33%
Question 10: A shirt was originally priced at $100. It is now on sale for $80. What is the percentage discount?
Answer: To calculate the percentage discount, we need to divide the amount of the discount by the original price and multiply by 100:
percentage discount = (amount of discount / original price) * 100
So, in this case, we have:
percentage discount = ($100 - $80) / $100 * 100 = 20%
Question 1: What is 20% of 100?
(A) 20 (B) 30 (C) 40 (D) 50
Answer: (A)
Explanation: Percentage means “out of one hundred,” so 20% of 100 is equal to 20/100 * 100 = 20.
Question 2: A shirt costs $100. If the shirt is discounted by 20%, how much will it cost now?
(A) $80 (B) $90 (C) $100 (D) $110
Answer: (A)
Explanation: To find the discounted price, multiply the discount by the original price and then subtract the product from the original price. So, the discounted price is 20/100 * $100 – $100 = $20 – $100 = $80.
Question 3: A student scored 80 marks in a test out of a total of 100 marks. What is the student’s percentage score?
(A) 80% (B) 90% (C) 100% (D) 110%
Answer: (A)
Explanation: To find the percentage score, divide the marks scored by the total marks and then multiply by 100. So, the student’s percentage score is 80/100 * 100 = 80%.
Question 4: The price of a commodity has increased by 10%. If the original price of the commodity was $100, what is the new price?
(A) $110 (B) $115 (C) $120 (D) $125
Answer: (C)
Explanation: To find the new price, multiply the percentage increase by the original price and then add the product to the original price. So, the new price is 10/100 * $100 + $100 = $10 + $100 = $110.
Question 5: A population of 1000 people has 60% males. What is the number of females in the population?
(A) 400 (B) 500 (C) 600 (D) 700
Answer: (B)
Explanation: The number of females in the population is 100% – 60% = 40%. So, the number of females in the population is 40/100 * 1000 = 400.
Question 6: A shopkeeper buys an article for $100 and sells it for $120. What is his percentage profit?
(A) 20% (B) 25% (C) 30% (D) 35%
Answer: (B)
Explanation: To find the percentage profit, divide the profit by the cost price and then multiply by 100. So, the shopkeeper’s percentage profit is 20/100 * 100 = 20%.
Question 7: A student got 75 marks in a test out of a total of 100 marks. If the passing marks are 60%, did the student pass the test?
(A) Yes (B) No
Answer: (A)
Explanation: Since the student got 75 marks, which is more than the passing marks of 60, the student passed the test.
Question 8: The price of a commodity has decreased by 20%. If the new price of the commodity is $80, what was the original price?
(A) $100 (B) $110 (C) $120 (D) $130
Answer: (A)
Explanation: To find the original price, divide the new price by 1 – the percentage decrease and then multiply by 100. So, the original price is 80 / (1 – 20/100) * 100 = 80 / (1 – 0.2) * 100 = 80 / 0.8 * 100 = 100.
Question 9: A population of 2000 people has 40% females. What is the percentage of males in the population?
(A) 40% (B) 50% (C) 60% (D) 70%
Answer: (C)
Explanation: The percentage of males in the population is 100% – 40% = 60%.
Question 10: A company gives a discount of 10% on its products to its employees. If an employee buys a product for $100, how much does he pay after the discount?
(A) $90 (B) $95 (C) $100 (D) $105
Answer: (A)
Explanation: To find the discounted price, multiply the discount by the original price and then subtract the product from the original price. So, the discounted price is 10/100 * $100 – $100 = $10 – $100 = $90.
Question 11: A student scored 90 marks in a test out of a total of 100 marks. What is the student’s percentage score if the full marks for the test were 200?
(A) 45% (B) 50% (C) 90% (D) 100%
Answer: (C)
Explanation: To find the percentage score, divide the marks scored by the total marks and then multiply by 100. So, the student’s percentage score is 90/200 * 100 = 45%.
Question 12: The population of a city has increased by 25% in the last 10 years. If the current population of the city is 1 million, what was the population of the city 10 years ago?
(A) 800,000 (B) 900,000 (C) 1 million (D) 1.25 million
Answer: (B)
Explanation: To find the population of the city 10 years ago, divide the current population by 1 + the percentage increase and then multiply by 100. So, the population of the city 10 years ago is 1,000,000 / (1 + 25/100) * 100 = 1,000,000 / (1.25) * 100 = 800,000.
Question 13: A shopkeeper buys an article for $100 and sells it for $150. What is his percentage markup?
(A) 50% (B) 60% (C) 70% (D) 80%
Answer: (C)
Explanation: To find the percentage markup, divide the markup by the cost price and then multiply by 100. So, the shopkeeper’s percentage markup is 50/100 * 100 = 50%.
Question 14: A student got 60 marks in a test out of a total of 100 marks. If the passing marks are 40%, did the student pass the test?
(A) Yes (B) No
Answer: (A)
Explanation: Since the student got 60 marks, which is more than the passing marks of 40, the student passed the test.
Question 15: A company gives a commission of 10% on its sales to its salespeople. If a salesperson sells a product for $100, how much commission does he earn?
(A) $10 (B) $15 (C) $20 (D) $25
Answer: (A)
Explanation: To find the commission earned, multiply the commission rate by the sales price. So, the salesperson earns a commission of 10/100 * $100 = $10.
Question 1: A shopkeeper gives a discount of 10% on a product which costs Rs.1000. What is the S.P. of the product?
(A) Rs.900 (B) Rs.950 (C) Rs.1000 (D) Rs.1050
Answer: (A)
Explanation: S.P. = Rs.[1000 – (10/100 * 1000)] = Rs.900
Question 2: A student scored 75 marks out of 100 marks in a test. What is her percentage score?
(A) 75% (B) 80% (C) 85% (D) 90%
Answer: (A)
Explanation: Percentage score = (75/100 * 100) % = 75 %
Question 3: The population of a town has increased by 20% in the last 10 years. If the current population of the town is 100000, what was the population of the town 10 years ago?
(A) 80000 (B) 90000 (C) 100000 (D) 120000
Answer: (A)
Explanation: Population 10 years ago = (100000 * 100 / 120) = 80000
Question 4: A shopkeeper buys an article for Rs.100 and sells it for Rs.120. What is his profit percentage?
(A) 20% (B) 25% (C) 30% (D) 35%
Answer: (B)
Explanation: Profit percentage = [(120 – 100) / 100 * 100] % = 20%
Question 5: A company gives a bonus of 10% on the salary of its employees. If the salary of an employee is Rs.10000, what is the bonus he receives?
(A) Rs.1000 (B) Rs.1500 (C) Rs.2000 (D) Rs.2500
Answer: (A)
Explanation: Bonus = (10/100 * 10000) = Rs.1000