Income of Amit in 2019 was ₹25,600. He gets an increment of 10% every year.…
2025
Income of Amit in 2019 was ₹25,600. He gets an increment of 10% every year. What was his income (in ₹) in 2021?
- A.
30,720
- B.
30,976
- C.
28,160
- D.
25,600
Show answer & explanation
Correct answer: B
Concept: When a quantity increases by r% every year for n years, each year’s increase is calculated on the previous year’s already-increased value, not on the original value, so the final value equals Initial × (1 + r/100)n — the same compounding principle used in compound interest.
Application: 2019 to 2021 spans 2 years, so the 10% increment applies twice in succession on Amit’s income:
Growth factor for one 10% increase = 1 + 10/100 = 1.10.
Income at the end of 2020 = ₹25,600 × 1.10 = ₹28,160.
Income at the end of 2021 = ₹28,160 × 1.10 = ₹30,976.
Cross-check: Applying the compounding formula directly, ₹25,600 × (1.10)2 = ₹25,600 × 1.21 = ₹30,976, which matches the step-by-step result — confirming Amit’s income in 2021 was ₹30,976.