a sum amounts to rs . 3087 in 2 years at the rate of 5 % p . a . if interest was compounded yearly then what was the principal ?
"ci = 3087 , r = 5 , n = 2 ci = p [ 1 + r / 100 ] ^ 2 = p [ 1 + 5 / 100 ] ^ 2 3087 = p [ 21 / 20 ] ^ 2 3087 [ 20 / 21 ] ^ 2 2800 answer : e"
divide(3087, power(add(divide(5, const_100), const_1), 2))