Question

tim abcd biet abcd-abc-ab-a=2086

Answer 1

abcd-abc-ab-a=2086

1000a+100b+10c+d-100a-10b-c-10a-b-a=2086

(1000a-100a-a)+(100b-10b-b)+(10c-c)+d=2086

899a+89b+9c+d=2086

=>abcd=2323

Answer 2

abcd-abc-ab-a = 2086

1000a+100b+10c+d-100a-10b-c-10a-b-a = 2086

889a + 89b + 9c + d = 2086

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