TCS NQT Guide TCS NQT Numerical AbilityPercentages: Concept, Tricks, and TCS Questions

Percentages: Concept, Tricks, and TCS Questions

Learn core concepts, essential formulas, and attempt practice questions designed on the latest TCS NQT testing patterns.

Key Concepts & Formulas

1Percentage Change = (Difference / Original Value) * 100%.
2If A is x% more than B, then B is [x / (100 + x)] * 100% less than A.
3If value increases by x% and then decreases by y%, Net Change = x - y - (xy / 100) %.

Practice Question 1

If the price of sugar increases by 25%, by what percent must a household reduce its consumption to keep the expenditure same?

A) 20%

B) 25%

C) 16.67%

D) 15%

Correct Answer: A) 20%

Step-by-step Solution: Reduction in consumption = [x / (100 + x)] * 100% = [25 / 125] * 100 = 20%.

Practice Question 2

A salary is first increased by 10% and then decreased by 10%. What is the net change in salary?

A) 1% decrease

B) 1% increase

C) No change

D) 2% decrease

Correct Answer: A) 1% decrease

Step-by-step Solution: Net Change = x - y - (xy / 100)% = 10 - 10 - (10 * 10 / 100) = -1%. A negative sign indicates a decrease of 1%.

Remember that successive percentage changes are not simple additions.