A and B are two natural numbers (A and B are not equal to 0), if (5/6) of A is exactly (1/4) of B, then what is the minimum value of the sum of A and B?
A、B两个自然数(A、B均不等于0)，如果A的(5/6)恰好是B的(1/4)，那么A、B之和的最小值是多少．
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