-
From 1980-1990, the population of a country increased by 20%. From 1990-2000, the population of the country increased by 20%. From 2000-2010, the population of the country increased by 20%.
Then the overall increased population (in percentage) of the country from 1980-2010 was
-
- 72.2 %
- 60 %
- 72.8 %
- 62.8 %
Correct Option: C
Using Rule 7,
Single equivalent increase for 20% and 20%
| = |  | 20 + 20 + |  | % = 44% | |
| 100 |
Single equivalent increase for 44% and 20%
| = | | 44 + 20 + | | % | |
| 100 |
= (64 + 8.8) % = 72.8%
