2)
1/5 × 2/3 = 2/15 → 2/15
4/7 × 5/3 = ( 4×5) /(7×3) = 20 /21 → 20/21
5/9 × 2/7 = ( 5 ×2) / ( 9×7) = 10 /63 → 10/63
5 × 3/4 = ( 5×3)/4 = 15 /4 ↔ 15 /4
2/5 × 3 = ( 2×3) /5 = 6/5 → 6/5
4/3 × 1/4 = 1/3 → 1/3
→ am simplificat pe 4 cu 4
5/2 × 4/5 = 2 → 2
→ simplific pe 5 cu 5 = 2/1=2