a sum of money at simple interest amounts to rs . 825 in 3 years and to rs . 830 in 4 years . the sum is ?
"s . i . for 1 year = ( 830 - 825 ) = rs . 5 s . i . for 3 years = 5 * 3 = rs . 15 principal = ( 825 - 15 ) = rs . 810 . answer : d"
subtract(825, divide(multiply(subtract(830, 825), 3), 4))