​Andy's utility function for goods X and Y is linear and is given by​ U(X,Y) = 2X​ + 3Y. Based on this utility​ function, we can conclude that goods X and Y are perfect substitutes for Andy. The price of X is​ $4, the price of Y is​ $8, and​ Andy's income is​ $40. To maximize his​ utility, Andy should purchase 10 units of X and 0 units of Y. ​(Enter your responses as real numbers rounded to one decimal​ place.)