Răspuns:
5.a)8/21×8 3/4=2/7×8=16/7
c)2 1/4×20/27=9/4×20/27=5/3
6.a)3 4/15×1 3/7=49/15×3/7=7/5
c) 2 7/9×1 7/20=25/9×7/20=5/9×7/4=35/36
Sper ca te-am ajutat!;)