Завдання 1101 - 1200 » 1130

Обчисли: 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 + 7)/8 = 13/8 = 15/8; 3) – 5/16 – 7/12 = – 5/16 + (–7/12) = – (15 + 28)/48 = – 43/48; 4) – 7/12 – (–8/15) = – 7/12 + 8/15 = – 35/60 + 32/60 = – 3/60 = – 1/20.