math
posted by Anonymous .
in the lab, tom has two solutions that contain alcohol and is mixing them with each other. he uses 300 millilters less of solution A than solution B. solution A is 10% alcohol and solution B is 13% alcohol. How many millilters of solution B does he use, if the resulting mixture has 269 millilters of pure alcohol?

let Vb be the volume of solution B
Va*.1+Vb*.13=269
(Vb300)*.1+Vb*.13=269
solve for Vb