Question

tim so abc biet 5abc-abc5= 1215

Answer 1

Ta có : 5abc - abc5 = 1215

=> (5000 + abc) - (abc0 + 5) = 1215

=> 5000 + abc - abc x 10 - 5 = 1215

=> (5000 - 5) + abc (1 - 10) = 1215

=> 4995 - abc x 9 = 1215

=> abc x 9 = 4995 - 1215

=> abc x 9 = 3780

=> abc = 420

Answer 2

la 420 do ban