34/13 x 15 3/41 - 3 4/13 х 2 3/41= (2 3/4 + 4 1/8) х 1 5/11= 1 2/5 х (1 1/14 - 5/7) =

(23 / 4 + 41 / 8) × 15 / 11  = 14,82954545
3 4\13×15 3\41-3 4\13×2 3\41=43/13*618/41-43/13*85/41=43/13(618/41-85/41)=43/13*533/41=43*41/41=43                    
12 / 5 × (11 / 14 – 5 / 7)  = 0,1714285714