Va rog!! Am nevoie urgent!

Răspuns:
14/27÷8/3÷(-7/15)=14/27×3/8×(-15/7)= -5/12
-12/49÷15/14÷(-20/21)=-12/49×21/20×14/15=-126/525
-40/27÷(-20/9)÷(-10/21)=-40/27×(-9/20)×(-21/10)=7/5
sper ca nu am greșit la simplificare