(2/7 + 5/21) ÷ (1 4/7) = (6/21 + 5/21) ÷ (11/7) = 11/21 ÷ 11/7 = 11/21 * 7/11 = 1/3

(8/11 + 3/22) ÷ (5/11) = (16/22 + 3/22) ÷ (5/11) = 19/22 ÷ 5/11 = 19/22 * 11/5 = 209/110 = 1.9.