Question

17. a) Câte numere naturale de 2 cifre folosesc în scrierea lor cifra 3?
b) Câte numere naturale de 3 cifre încep cu 322
c) Câte numere naturale de 3 cifre se termină cu 3?

Answer 1

Răspuns:

a.23,32,13,31,43,34,53,35,36,73,63,37,83,38,39,93

c.103,113,123,133,143,153,163,333,303,173,183,193,403,203,503,603,703,803,903,873,983,723,273,453,563,763,753,653,733,833,933,793,233,443,553,663,773,883,993

Answer 2

Răspuns:

a) 13,23,33,43,53,63,73,83,93,31,32,34,35,36,37,38,39=17 nr.

b) 322=1

c)103,113,123,133,143,153,163,173,183,193...903,913,923,933,943,953,963,973,983,993=9×10=900 de nr.