приведите дробь к НОК.
1) 1/4 и 1/10
2)1/6 и 1/9
3) 1/10 и 1/25
4)1/30 и 1/50
5) 1/70 и 1/60

1) 4 = 2 * 2     10 = 2 * 5     НОК = 2 * 2 * 5 = 20
1/4 = 5/20 и 1/10 = 2/20

2) 6 = 2 * 3     9 = 3 * 3       НОК = 2 * 3 * 3 = 18
1/6 = 3/18 и 1/9 = 2/18

3) 10 = 2 * 5     25 = 5 * 5     НОК = 2 * 5 * 5 = 50
1/10 = 5/50 и 1/25 = 2/50

4) 30 = 2 * 3 * 5       50 = 2 * 5 * 5       НОК = 2 * 3 * 5 * 5 = 150
1/30 = 5/150 и 1/50 = 3/150

5) 70 = 2 * 5 * 7       60 = 2 * 2 * 3 * 5       НОК = 2*2*3*5*7 = 420
1/70 = 6/420 и 1/60 = 7/420