7abcde = 5 x abcde7
700000 + abcde = abcde x 10 + 7
700000 - 7 = abcde x 9
699993 = abcde x 9
699993 : 9 = abcde
77777 = abcde
7abcde = 5.abcde7
700000 + abcde = 5(10.abcde + 7)
700000 + abcde = 50.abcde + 35
700000 - 35 = 50.abcde - abcde
699965 = 49.abcde
abcde = 699965 : 49
abcde = 14285
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