The two numbers A and B are natural numbers that are not 0. If (5/6) of A is exactly (1/4) of B, what is the minimum value of the sum of A and B?
甲、乙两数是不为0的自然数，如果甲数的(5/6)恰好是乙数的(1/4)，那么甲、乙两数之和的最小值是多少
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