Найдите значение выражения: (3/16+а)-3/8, а=5/12; (4/15+5/8)-с, с=3/5; (b+5/6)-3/4,...

(3/16 + а) - 3/8 = (3/16 + 5/12) - 3/8 = (9+20)/48 - 3/8 = 29/48 - 3/8 = (29-18)/48 = 11/48
(4/15 + 5/8) - с = (4/15 + 5/8) - 3/5 = (32+75)/120 - 3/5 = 107/120 - 3/5 = (107-72)/120 = 35/120 = 7/24
(в + 5/6) - 3/4 = (11/12 + 5/6) - 3/4 = (11+10)/12 - 3/4 = 21/12 - 3/4 = (21-9)/12 = 12/12 = 1
(1/5 + д) - 9/20 = (1/5 + 13/16) - 9/20 = (16+65)/80 - 9/20 = 81/80 - 9/20 = (81-36)/80 = 45/80 = 9/16