Let 4 yuan be x 8, Z=8 yuan is y, 10 yuan is z, x, y, and the minimum value of z is 1, X+Y+Z = 15, 4x+8y+10z =/kloc-0. When x = 65,438+000,20, the solution is unqualified; It is known that z should be less than 8; Let z = 7, 4x+8y = 30 and x+y = 8. These two equations are simultaneous and the solution is negative, so this solution is unqualified. Let z = 6, 4x+8y = 40 and x+y = 9. These two equations are simultaneous, and the solutions are y = 1 and x = 8. This solution is qualified. Let Z=5, 4x+8y=50, x+y= 10, these two equations are simultaneous, and the solution is non-integer, which is unqualified; According to this method, let Z=4, Z=3, Z=2, Z= 1 respectively, and solve simultaneous equations, and get Z=4, Z=2, with qualified solutions.