Ответ:
7 1/2
Пошаговое объяснение:
1) 6 3/8 * 1 7/17 = 51/8 * 24/17 = 3/1 * 3/1 = 9/1 = 9
2) 2 3/8 : 1 1/4 = 19/8 : 5/4 = 19/8 * 4/5 = 19/2 * 1/5 = 19/10 = 1 9/10
3) 9 - 1 9/10 = 8 10/10 - 1 9/10 = 7 1/10
4) 7 1/10 + 2/5 = 7 1/10 + 4/10 = 7 5/10 = 7 1/2
