Percentage Tricks for Exams: Solve Math Faster
In competitive exams like the SAT, GRE, GMAT, or banking exams, time is your most precious resource. While we build robust calculators at CalcMate for everyday use, you can't bring our tools into an exam hall. You need to rely on mental math.
Here are the most powerful percentage tricks that will help you solve problems in seconds instead of minutes.
Trick #1: x% of y = y% of x
This is arguably the most powerful yet underutilized mathematical property of percentages. The operation is entirely reversible!
Example: What is 16% of 50?
Calculating 16% of 50 in your head sounds annoying. But if you reverse it to 50% of 16, the answer is instantly obvious. Half of 16 is 8. Therefore, 16% of 50 is also 8!
Trick #2: Memorize Fraction to Percentage Conversions
Every fast test-taker has standard fractions memorized as percentages. When you see a percentage in a word problem, immediately convert it to its fraction form to simplify the multiplication.
- 1/2 = 50%
- 1/3 = 33.33%
- 1/4 = 25%
- 1/5 = 20%
- 1/6 = 16.66%
- 1/8 = 12.5%
- 1/10 = 10%
Example: Calculate 12.5% of 64.
Instead of complex decimal multiplication, recognize that 12.5% is exactly 1/8. So the problem simply becomes 64 / 8. The answer is 8.
Trick #3: The 10% and 1% Building Blocks
You can find 10% of any number simply by moving the decimal point one place to the left. You can find 1% by moving it two places. Use these as building blocks to construct any percentage.
Example: What is 23% of 400?
- Find 10% of 400 = 40
- Find 1% of 400 = 4
- Build the answer: (10% × 2) + (1% × 3)
- (40 × 2) + (4 × 3) = 80 + 12 = 92
Practice Makes Perfect
While tricks are great, nothing beats practice. When you are studying at home, verify your mental math using calculators. If you are converting grades, check out our CGPA to Percentage Calculator to see how percentages apply in real-world educational scenarios.