40 : 2 = 20 180 : 2 = 90 60 : 2 = 30 140 : 2 = 70
20 : 2 = 10 90 : 2 = 45 30 : 2 = 15 70 : 2 = 35
10 : 2 = 5 45 : 3 = 15 15 : 3 = 5 35 : 5 = 7
5 : 5 = 1 15 : 3 = 5 5 : 5 = 1 7 : 7 = 1
5 : 5 = 1
40 = 2 * 2 * 2 * 5
180 = 2 * 2 * 3 * 3 * 5
60 = 2 * 2 * 3 * 5
140 = 2 * 2 * 5 * 7
НОК (40; 180; 60; 140) = 2 * 2 * 2 * 3 * 3 * 5 * 7 = 2520 - наименьшее общее кратное
2520 : 40 = 63; 2520 : 180 = 14; 2520 : 60 = 42; 2520 : 140 = 18
ответ: НОК = 2520.
4 2/3 * 6 - 2 23/42 * 3 1/13 + 2 1/8 * 1 29/51 = 23 45/91
1) 4 2/3 * 6 = 14/3 * 6 = 28
2) 2 23/42 * 3 1/13 = 107/42 * 40/13 = 2140/273 = 7 229/273
3) 2 1/8 * 1 29/51 = 17/8 * 80/51 = 10/3 = 3 1/3
4) 28 - 7 229/273 = 27 273/273 - 7 229/273 = 20 44/273
5) 20 44/273 + 3 1/3 = 20 44/273 + 3 91/273 = 23 135/273 = 23 45/91
(5 3/10 - 3 4/5 * 13/38) * 5/84 + 2 1/12 * 4/15 = 50/63
1) 3 4/5 * 13/38 = 19/5 * 13/38 = 13/10 = 1 3/10
2) 5 3/10 - 1 3/10 = 4
3) 4 * 5/84 = 20/84 = 5/21
4) 2 1/12 * 4/15 = 25/12 * 4/15 = 5/9
5) 5/21 + 5/9 = 15/63 + 35/63 = 50/63