2016 · Q14
For which time intervals, is the percentage rise of population the same for the following data? Period Population 1970 40,000 1980 50,000 1990 60,000 2000 72,000 2010 80,000
General Mental Ability, Quantitative Aptitude and StatisticsNumber system and arithmetic
- A1970-80 and 1980-90
- B1980-90 and 1990-2000
- C2000-2010 and 1990-2000
- D1980-90 and 2000-2010
Explanation
Percentage rise = (new − old) ÷ old × 100. 1970–80: 10,000/40,000 = 25%; 1980–90: 10,000/50,000 = 20%; 1990–2000: 12,000/60,000 = 20%; 2000–10: 8,000/72,000 ≈ 11.1%. The 20% rise occurs for both 1980–90 and 1990–2000. Hence (B).