The sum of the ages of A, B, and C is 64 years old, the sum of the ages of B, C, and D is 36 years, and the sum of the ages of A and D is twice the sum of the ages of B and C. What is the sum of the ages of the four of them?
甲、乙、丙三人的年龄之和是64岁，乙丙丁三人的年龄之和是36岁，甲丁的年龄之和是乙丙年龄和的2倍，他们四人年龄和是多少？
<result>75</result>