Ajutooor ,dau coroana .Rezolvați ce este încercuit va rog

4/5=8/10=12/15=40/50=400/500
48/36=24/18=12/9=4/3=40/30
35/42=5/7=50/70=10/14=15/21
55/99=5/9=10/18=15/27=50/90=25/45
8b
o jumatate=1/2
deci (1/2) *36=18 (sa, fara fractii ,36:2=18)
(5/6) *42=5*7=35
un sfert=1/4
deci (1/4) din (4/5) =(1/4)*(4/5) =1/5
(1/3) *(9/13)=9/93*13)=(3*3)/(3*13)=3/13
10
50% =50/100=1/2
1/2 din56=56:2=28
75%=75/100=3/4
3/4din 576=3*576:4=3*144=432
25%=25/100=1/4
1/4 din 38,6=38,6:4=19,3:2=9,65
50% din 45% din 540=45% din50% din 540=45%din270=(45/100) din270=
45/10 din27=9/2 din27=9*27/2=9*13,5=121,5