Which expression is equivalent

Achemist has 200 ml of a 10% sucrose solution. she adds x ml of a 40% sucrose solution. the percent concentration, y, of the final mixture is given by the rational function: the chemist needs the concentration of the final mixture to be 30%. how many milliliters of the 40% solution should she add to the 10% solution to get this concentration?

The hawaiian alphabet has 12 letters. how many permutations are posible for each number of letters?

Find the equation of the line with slope =8 and passing through (6,53) write your equation in the form y=mx+b