after paying a 10 percent tax on all income over $ 3000 , a person had a net income of $ 12000 . what was the income before taxes ?
let x be the income over 3000 then ( x - x / 10 ) + 3000 = 12000 = > x = 10000 therefore income before taxes = 10000 + 3000 = 13000 option ( b )
divide(subtract(12000, multiply(divide(10, const_100), 3000)), subtract(const_1, divide(10, const_100)))