-0,2= - 2/10= -1/5
(-1/5)⁻¹= 1/(1/5)¹= 1 * 5/1=5
10⁻²= 1/10²= 1/100
10⁻¹= 1/10
0,125=125/1000= 1/8
0,1(6)= (16-1)/90= 15/90=1/6
3,6= 3 intregi 6/10= 3 intregi 3/5= 18/5
5 * 1/100 + 1/8 :1/10 -1/6 * 18/5=
=1/20 + 1/8 * 10/1 - 3/5=
= 1/20 -5/4 -3/5 aducem la acelasi numitor
= (1-25-12)/20= =(1-37)/20= -36/20= -9/5
