The population of a variety of tiny bush in an experimental field increased by 10% in the first year, increased by 8% in the second year but decreased by 10% in the third year. If the present number of bushes in the experimental field is 26730, then the number of bushes in the beginning was :

Number of bushes in the beginning :
$$\eqalign{ & = \frac{{26730}}{{\left( {1 + \frac{{10}}{{100}}} \right)\left( {1 + \frac{8}{{100}}} \right)\left( {1 - \frac{{10}}{{100}}} \right)}} \cr & = \left( {26730 \times \frac{{10}}{{11}} \times \frac{{25}}{{27}} \times \frac{{10}}{9}} \right) \cr & = 25000 \cr} $$