at what rate percent per annum will the simple interest on a sum of money be 6 / 5 of the amount in 10 years ?
"let sum = x . then , s . i . = 6 x / 5 , time = 10 years . rate = ( 100 * 6 x ) / ( x * 5 * 10 ) = 12 % answer : e"
divide(multiply(divide(6, 5), const_100), 10)