A is the average marks of a group of 10 students in a class and A+8 is the average of a group of 15 students which includes the group of 10 students as given. The total marks obtained by the group of 10 students is X and the total marks obtained by the group of 15 students is Y. If X : Y = 3 : 5, then the value of A + X + Y is _________.