Сделайте деянья 1)9+1целая3/4-2/5; 2)3целых5/12-4/5+31/60; 3)6целых5/9+3-7/12; 4)8целых 7/15-5целых3/4+6

1) 9 + 1 3/4 - 2/5 = 9 + (1 * 4 + 3)/4 - 2/5 = 9 + 7/4 - 2/5 = (9 * 20)/20 + (7 * 5)/20 - (2 * 4)/20 = 180/20 + 35/20 - 8/20 = (180 + 35 - 8)/20 = 207/20 = 10.35.

2) 3 5/12 - 4/5 + 31/60 = (3 * 12 + 5)/12 - 4/5 + 31/60 = 41/12 - 4/5 + 31/60 = (41 * 5)/60 - (4 * 12)/60 + 31/60 = 205/60 - 48/60 + 31/60 = (205 - 48 + 31)/60 = 188/60 = 3 2/15.

3) 6 5/9 + 3 - 7/12 = (6 * 9 + 5)/9 + 3 - 7/12 = 59/9 + 3 - 7/12 = (59 * 4)/36 + (3 * 36)/36 - (3 * 7)/36 = 236/36 + 108/36 - 21/36 = (236 + 108 - 21)/36 = 323/36 = 8 35/36.

4) 8 7/15 - 5 3/4 + 6 = (8 * 15 + 7)/15 - (5 * 4 + 3)/4 + 6 = 127/15 - 23/4 + 6 = (127 * 4)/60 - (23 * 15)/60 + (60 * 6)/60 = 508/60 - 345/60 + 360/60 = (508 - 345 + 360)/60 = 523/60 =

8 43/60.