36. 15\% of 240 = 15100 240 = 36.

The price of an item is increased by 20% and then decreased by 20%. What is the net change?

4% decrease. Net change = 20 - 20 - 20 20100 = -4, i.e. a 4% decrease.

If A's salary is 25% more than B's, then B's salary is what percent less than A's?

20%. Take B = 100, so A = 125. B is less than A by 25125 100\% = 20\%.

In an election between two candidates, the winner secured 60% of the votes and won by 900 votes. How many votes were cast in total?

4500. The winning margin is 60\% - 40\% = 20\% of the votes, and this equals 900. So the total is 9000.20 = 4500.

AI-guided practice

Quantitative Aptitude · Averages, Ratios & Percentages

Percentage — Questions & Answers

Percentage is the language of profit, interest, data interpretation and more. Master percentage increase and decrease, successive changes, and converting between a percentage, a fraction and a decimal.

5 solved questions
·
Step-by-step AI walkthroughs
·
Key formulas included

Key formulas

$x\%$ of $N = \dfrac{x}{100}\times N$ ; and $A$ as a percent of $B$ is $\dfrac{A}{B}\times 100\%$
Percentage change $= \dfrac{\text{new} - \text{old}}{\text{old}}\times 100\%$
Successive changes of $a\%$ then $b\%$ : net $= a + b + \dfrac{ab}{100}\ \%$

5 solved Percentage questions

Try each question first — tap an option to check your answer, or open Learn step by step for a guided walkthrough.

01
What is 15% of 240?
3 steps · reveal one at a time
1. Step 1: Understand percentage
  A percentage means 'out of one hundred'. So, $15\%$ can be written as the fraction $\frac{15}{100}$ or the decimal $0.15$ .
2. Step 2: Set up calculation
  To find $15\%$ of $240$ , we multiply the fractional or decimal form of the percentage by $240$ . This gives us the expression $\frac{15}{100} \times 240$ .
3. Step 3: The answer
  Now, perform the multiplication: $\frac{15}{100} \times 240 = \frac{15 \times 240}{100} = \frac{3600}{100} = 36$ . So the answer is (A) 36. This is the value we calculated.
02
45 is what percent of 180?
5 steps · reveal one at a time
1. Step 1: Understand the Question
  We need to find what percentage 45 represents when compared to 180. This is a common type of percentage problem: "A is what percent of B?".
2. Step 2: Formulate the Equation
  To find what percent "A" is of "B", we use the formula $\frac{A}{B} \times 100\%$ . Here, A is 45 and B is 180. So, we need to calculate $\frac{45}{180} \times 100\%$ .
3. Step 3: Perform the Calculation
  First, divide 45 by 180: $\frac{45}{180}$ . This fraction simplifies to $\frac{1}{4}$ . Now, convert this fraction to a percentage by multiplying by 100%.
4. Step 4: Calculate the Percentage
  Multiplying $\frac{1}{4}$ by 100% gives us $0.25 \times 100\% = 25\%$ . This means 45 is 25% of 180.
5. Step 5: The answer
  So the answer is (A) 25%. This is because 45 divided by 180, then multiplied by 100%, equals 25%.
03
The price of an item is increased by 20% and then decreased by 20%. What is the net change?
5 steps · reveal one at a time
1. Step 1: Understand the changes
  We are told an item's price is first increased by 20% and then decreased by 20%. We need to find the overall net change in price. This is a common type of percentage change problem.
2. Step 2: Recall the formula
  For two successive percentage changes, $x\%$ and $y\%$ , the net percentage change is given by the formula: $x + y + \frac{xy}{100}$ . Remember that an increase is positive and a decrease is negative.
3. Step 3: Apply the values
  In this problem, the first change is an increase of $20\%$ , so $x = 20$ . The second change is a decrease of $20\%$ , so $y = -20$ . Substitute these values into the formula: $20 + (-20) + \frac{20 \times (-20)}{100}$ .
4. Step 4: Calculate the net change
  Let's simplify the expression: $20 - 20 - \frac{400}{100}$ . This becomes $0 - 4$ . So, the net change is $-4$ . A negative sign indicates a decrease.
5. Step 5: The answer
  So the answer is (C) 4% decrease. The calculation shows a net change of $-4$ , which means the price has decreased by $4\%$ overall.
04
If A's salary is 25% more than B's, then B's salary is what percent less than A's?
5 steps · reveal one at a time
1. Step 1: Assign B's Salary
  To make calculations easy, let's assume B's salary is $100$ . This is a common strategy for percentage problems, as percentages are based on 100.
2. Step 2: Calculate A's Salary
  A's salary is 25% more than B's. So, A's salary is $100 + 25\% \text{ of } 100 = 100 + 25 = 125$ .
3. Step 3: Find the Difference
  Now we need to find how much less B's salary is than A's. The difference between A's and B's salary is $125 - 100 = 25$ .
4. Step 4: Calculate Percentage Less
  To find what percent less B's salary is than A's, we compare the difference to A's salary. The percentage is $\frac{\text{Difference}}{\text{A's Salary}} \times 100\% = \frac{25}{125} \times 100\% = 20\%$ .
5. Step 5: The answer
  So the answer is (C) 20%. B's salary is 20% less than A's when A's is 25% more than B's.
05
In an election between two candidates, the winner secured 60% of the votes and won by 900 votes. How many votes were cast in total?
4 steps · reveal one at a time
1. Step 1: Find Loser's Votes
  The winner secured $60\%$ of the votes. Since there are only two candidates, the other candidate (the loser) must have secured $100\% - 60\% = 40\%$ of the total votes.
2. Step 2: Calculate Vote Margin
  The winner won by a certain percentage of votes. This winning margin is the difference between their percentages: $60\% - 40\% = 20\%$ of the total votes.
3. Step 3: Determine Total Votes
  We know that this $20\%$ margin corresponds to 900 votes. To find the total votes, we divide the margin votes by the margin percentage: $\frac{900}{0.20} = 4500$ votes.
4. Step 4: The answer
  So the answer is (B) 4500. This is the total number of votes cast in the election, where 20% of this total equals 900 votes.

Free to start

Get exam-ready on Percentage

Generate fresh percentage practice sets in Test Studio, get step-by-step AI explanations the moment you slip, and close the gaps in Socrative Mode.

Start practising free Browse all topics

Step-by-step AI solutions
Fresh practice sets on demand
Guided Socrative Mode drills

Key formulas

5 solved Percentage questions

Get exam-ready on Percentage

More in Averages, Ratios & Percentages