Explicație pas cu pas:
3/2 ,13/6 ,2/3 (nc=6)
3×3/6 ,13/6 , 2×2/6
6/6 , 13/6 , 4/6
4/6 < 6/6 < 13/6
2/3 < 3/2 < 13/6
a) 2/3 × 13/6 =2×13/3×6=26/18 =26:2/18:2=13/9
b) (2/3 + 3/2)×(13/6 - 2/3)=
=(4+6/6)×(13-4/6)
=10/6 × 9/6 =90/36=90:18/36:18=5/2
