4,5=45/10=9/2
2,7=27/10
27/10*(x:3/2-7/2)=14/33-9/2 amplificam pe 14/33 cu 2 si pe 9/2 cu 33
27/10*(x:3/2-7/2)=28/66-297/66
27/10*(x:3/2-7/2)= -269/66
x:3/2-7/2= -269/66*10/27
x:3/2-7/2= -2690/1782
x:3/2= -2690/1782+7/2 amplificam pe 7/2 cu 1782 si pe prima fractie cu 2
x:3/2= -5380/3564+12474/3564
x:3/2=7094/3564
x=7094/3564*2/3
x=7094/5346