The three numbers of A, B, and C are 603, 939, and 393 respectively. The remainder obtained by dividing A by A is twice the remainder obtained by dividing B by A, and the remainder obtained by dividing B by A is twice the remainder obtained by dividing C by A. How much is A equal to?
甲、乙、丙三数分别为603，939，393．某数A除甲数所得余数是A除乙数所得余数的2倍，A除乙数所得余数是A除丙数所得余数的2倍．求A等于多少？
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