Abag contains 5 yellow marbles, 7 pink marbles, and 3 purple marbles. gordon selects a marble without looking. what is the probability that he selects a yellow marble or a purple marble?

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?