Номер 1130

1) – 1/2 – (–7/18) = – 1/2 + 7/18 = – 9/18 + 7/18 = –2/18 = –1/9

2) 3/4 – (–7/8) = 3/4 + 7/8 = 6/8 + 7/8 = 13/8 = 15/8

3) –5/16 – 7/12 = –5/16 + (–7/12) = –(15/48 + 28/48) = –43/48

4) –7/12 – (–8/15) = –7/12 + 8/15 = –35/60 + 32/60 = –3/60 = –1/20