Explications étape par étape:
1)
=(16×2)/(15×2) - (2×6)/(5×6) + (7×10)/(3×10) + (3×3)/(10×3)
= 32/30 - 12/30 + 70/30 + 9/30
= 20/30 + 70/30 + 9/30
= 99/30 = 33/10
2)
=7/4 + 9/4 + (3×4)/4
= 16/4 + 12/4
= 28/4 = 7
3)
= 8/5 + (4×5)/5 - 1/5
= 8/5 + 20/5 - 1/5
= 27/5
