12.
a) abcd2=10002; a+b+c+d=1;
b) abcd3=10003; a+b+c+d=1 (am pus cam la fel fiindca nu zice sa fie distincte)
c) abcd5=99995; a+b+c+d=9×4=36;
d) abcd9=99999; a=b=c=d <=> 9=9=9=9;
e) abcd10=100010; 0×5×c+d=0×5×0+0= 0;
13.
a) 2954 : 2= 1477
b) 3+4+5=12; 18-12=6; a+b=6 =>
=> 34a5b=34056 (a=0, b=6);
=34155 (a=1, b=5);
=34254 (a=2, b=4);
=34353 (a=3, b=3);
=34452 (a=4, b=2);
=34551 (a=5, b=1);
=34650 (a=6, b=0).
*Sper ca te am ajutat!*
*Succes la scoala!*