Дроби к наименьшему общему знаменателю: 7/20 и 5/12 11/24 и 1/30 3/10 и 7 / 16 3/16 и 1/10 11/18 и 7/12 7/24 и 2/15 1/12 и 2/9 4/21 и 13/28 3/14 и 2/21 / дробная черта

1) 7/20= 7*3 / 20*3 = 21/60 И 5/12 = 5*5 / 12*5 = 25/60

2) 11/24 = 11*5 / 24*5 = 55/120 И 1/30 = 1*4 / 30*4 = 4/120

3) 3/10 = 3*8 / 10*8 = 24/80 И 7/16 = 7*5 / 16*5 = 35/80

4) 3/16 = 3*10 / 16*10 = 30/160 И 1/10 = 1*16 / 10*16 = 16/160

5) 11/18 = 11*4 / 18*4 = 44/72 И 7/12 = 7*6 / 12*6 = 42/72

6) 7/24 = 7*5 / 24*5 = 35/120 И 2/15 = 2*8 / 15*8 = 16 / 120

7) 1/12 = 1*3 / 12*3 = 3/36 И 2/9 = 2*4 / 9*4 = 8/36

8) 4/21 = 4*4 / 21*4 = 16/84 И 13/28 = 13*3 / 28*3 = 39/84

9) 3/14 = 3*3 / 14*3 = 3/42 И 2/21 = 2*3 / 21*2 = 6/42