a)0,8=8/10= 4/5
1,(6)=1 intreg 6/9=1 intreg 2/3= 5/3
0,2(7)= (27-2)/90= 25/90= 5/18
4/5 * (5x/3 -5/18)=5x/4 aducem la acelasi numitor in paranteza
4/5 * (30x-5)/18=5x/4
2/5 * 5(6x-1)/9=5x/4
2(6x-1)/9= 5x/4
(12x-1)/9=5x/4
48x-4=45x
48x-45x=4
3x=4
x=4/3
b)1,5=1 intreg 5/10= 1 intreg 1/2= 3/2
0,1(6)= (16-1)/90= 15/90= 1/6
4x/5= 3/2 * (1/6 * x/5 +10/9)
4x/5= 3/2 * (x/30+10/9) aducem la acelasi numitor in paranteza
4x/5= 3/2 * (3x+100)/90
4x/5 = (3x+100)/60
240x=15x-500
240x-15x= -500
225x= -500
9x= -20
x= -20/9
