Пошаговое объяснение:
1) 1 1/4 * 1 1/5 = 5/4 * 6/5 = 3/2
2) 1 1/7 * 1 1/8 = 8/7 * 9/8 = 9/7
3) 3/2 + 9/7 = 21/14 + 18/14 = 39/14 = 2 11/14
1) 12 4/5 * 3 3/4 = 64/5 * 15/4 = 48
2) 4 4/11 * 4 1/8 = 48/11 * 33/8 = 18
3) 48 - 18 = 30
Пошаговое объяснение:
1) 1 1/4 * 1 1/5 = 5/4 * 6/5 = 3/2
2) 1 1/7 * 1 1/8 = 8/7 * 9/8 = 9/7
3) 3/2 + 9/7 = 21/14 + 18/14 = 39/14 = 2 11/14
1) 12 4/5 * 3 3/4 = 64/5 * 15/4 = 48
2) 4 4/11 * 4 1/8 = 48/11 * 33/8 = 18
3) 48 - 18 = 30