the present worth of rs . 2310 due 2 years hence , the rate of interest being 15 % per annum , is :
"p . w . = rs . 100 x 2310 = rs . 1680 . 100 + 15 x 5 2 answer : b"
divide(2310, power(add(divide(15, const_100), const_1), 2))