Question

2)Aflati abc stiind ca impartind la 72 da restul 69, iar impartit la 60 da restul 57.

Answer 1

Fie nr abc=x
X:72=c rest 69
X:60=d rest 57
72c+69=60d+57
=> 72c+12=60d
6(12c+2)=60d
12c+2=10d
6c+1=5d
=> 6c + 1 = multiplu de 5
Dar 72c+69<1000
=> c<12
6c+1=5d
=> c=4, 9
=> abc=357, 717