Total rate of increase in population per annum = 10%
Initially, let the population be 1000
population after 3 yr = 1000(1 + 10/100)3
= (1000 x 11/10 x 11/10 x 11/10) = 1331
∴ Increase in percentage = [(1331 - 1000)/1000] x 100%
= (331/1000) x 100%
= 33.1%