The two numbers A and B are natural numbers, and both A and B are not zero. If (4/5) of A is exactly (1/3) of B, what is the minimum value of the sum of A and B?
甲、乙两数是自然数，且甲、乙都不为零，如果甲数的(4/5)恰好是乙数的(1/3)，那么甲、乙两数和的最小值是多少．
<result>17</result>