Percentage — The 5 Shortcuts That Cover Most Questions

Why Percentage Rules Every Exam

Percent means "per hundred". Writing 35% is the same as writing 35/100 or 0.35.

Percentage is the single most reused topic in Indian competitive exams. It sits underneath profit-loss, simple and compound interest, data interpretation, population growth and election questions. Master it once and you have quietly prepared four other chapters.

The one conversion you must be fluent in:

• ›To make a percent a decimal, divide by 100 → 42% = 0.42
• ›To make a decimal a percent, multiply by 100 → 0.075 = 7.5%

The base matters more than the number. "20% of what?" is always the first question to ask. Most wrong answers in exams come from taking the percentage of the wrong base, not from bad arithmetic.

1. What is 16⅔% of 5,400?

2. A price increases by 20% and then decreases by 20%. What is the net change?

3. If A's salary is 25% more than B's, then B's salary is how much less than A's?

4. The population of a town is 8,000 and grows at 10% per year. What will it be after 2 years?

5. 30% of 40% of 700 is:

6. A student scored 480 marks out of 600. What percentage is this?

7. If 12½% of a number is 96, the number is:

8. In an election between two candidates, the winner got 60% of the votes and won by 1,200 votes. How many votes were cast in total?