rendre les fraction irreductible 20/30 21/27 30/45 36/45 10/25 36/12 25/125 42/49 45/60 72/16 32/38 16/20 121/55 121/55 126/81 320/240 150/420 mrc

20/30 = 2/3

21/27 = 7/9

30/45 = 2/3

36/45 = 4/5 

10/25 =  2/5

36/12 =  6/2

25/125 = 1/5

42/49  = 6/7

45/60  =  3/4

72/16  =  9/2

32/38 =  16/19

16/20 = 4/5

121/55 =  11/5

126/81=  14/9

320/240 = 4/3

150/420= 5/14