the population of a town is 10000 . it decreases annually at the rate of 10 % p . a . what will be its population after 2 years ?
"10000 × 90 / 100 × 90 / 100 = 8100 answer : c"
subtract(subtract(10000, multiply(10000, divide(10, const_100))), multiply(subtract(10000, multiply(10000, divide(10, const_100))), divide(10, const_100)))