Răspuns:
rest 0
Explicație pas cu pas:
x:13=a,r7 => x=13a+7
y:13=b,r5 => y=13b+5
z:13=c,r5 =>z=13c+5
N=2x+3y+2z
N=2(13a+7)+3(13b+5)+2(13c+5)
N=2×13a+14+3×13b+15+2×13c+10
N=13(2a+3b+2c)+39
N=13(2a+3b+2c+3)
N:13=13(2a+3b+2c+3):13
N:13=2a+3b+2c+3, rest 0