(3/14+2/21)×(5/13+5/39) (8/25×15+1/2×4)×3/5

▪(3/14+2/21)×(5/13+5/39)=(9/42+4/42)×(15/39+5/39)=13/42 × 20/39 = 10/63
▪(8/25×15+1/2×4)×3/5=(24/5 + 2) × 3/5=(4 4/5 + 2) × 3/5=6 4/5 × 3/5 = 34/5 × 3/5 = 102/25 = 4 целых 2/25 = 4,08