8/15 ÷ 22/3 = 16/5 ÷ 22/3 = 16/5 × 3/22 = 24/55
23/5 ÷(5/9 + 5,3) = 414/527
1)5/9 + 5,3 = 5/9 + 5 3/10 = 5/9 + 53/10 = (5 × 10 + 53 × 9)/90 = (50 + 477)/90 = 527/90 = 5 77/90
2)23/5 ÷ 5 77/90 = 23/5 ÷ 527/90 = 23/5 × 90/527 = 414/527
(3,5 - 11/3) ÷ 2/13 = - 1 1/12
1)3,5 - 11/3 = 3 5/10 - 11/3= 35/10 - 11/3 = 7/2 - 11/3 =(7 × 3 - 11 × 2)/6 = (21 - 22)/6 = - 1/6
2) - 1/6 ÷ 2/13 = - 1/6 × 13/2 = - 13/12 = - 1 1/12