PREVIOUSLY ASKED IN:
PSC Miscellaneous Prelims 2018
Answer
33 1/3%
Explanation
Let B's salary be Rs. 100. Since A's salary is 25% less, A's salary is (100 - 25) = Rs. 75. Now, we need to find how much more B's salary (100) is compared to A's salary (75). The difference is 25. Therefore, the required percentage increase with respect to A's salary is (25 / 75) × 100 = 100/3 % = 33 1/3%.
Key Points
- > Always assume the base value (the one being compared against initially) as 100.
- > Shortcut Formula: If less by R%, then more % = [R / (100 - R)] × 100 %.
- > Here R = 25. Applying formula: (25 / 75) × 100 = 100/3 %.
- > 100/3 % translates to 33.33% or 33 1/3 %.
- > Conversely, if it was 25% MORE, the less % would be [25 / (100 + 25)] × 100 = 20%.
Additional Information
Percentage Decrease vs Increase Equivalents
| Less by % (A) | More by % (B) | Fraction Equivalent |
|---|---|---|
| 10% less | 11 1/9% more | 1/10 |
| 20% less | 25% more | 1/5 |
| 25% less | 33 1/3% more | 1/4 |
| 50% less | 100% more | 1/2 |
Memory Tips
- Fraction Rule: 25% less means -1/4. To find the positive counterpart, subtract the numerator from the denominator: +1/(4-1) = +1/3. 1/3 is exactly 33 1/3%.