barbata invests $ 3000 in the national bank at 5 % . how much additional money must she invest at 8 % so that the total annual income will be equal to 6 % of her entire investment ?
"let the additional invested amount for 8 % interest be x ; equation will be ; 3000 + 0.05 * 3000 + x + 0.08 x = 3000 + x + 0.06 ( 3000 + x ) 0.05 * 3000 + 0.08 x = 0.06 x + 0.06 * 3000 0.02 x = 3000 ( 0.06 - 0.05 ) x = 3000 * 0.01 / 0.02 = 1500 ans : ` ` e ' '"
divide(subtract(multiply(divide(6, const_100), 3000), multiply(3000, divide(5, const_100))), subtract(divide(8, const_100), divide(6, const_100)))