-1 7/8 · 1 1/3 = -15/8 · 4/3 = -15·4 /(8·3) = -2 1/2
1 2/3:(-3 1/3) = - 5/3 : 10/3 = -5·3/(3·10) = -1/2
1)-1 ⁷/₈ * 1 ¹/₃= -¹⁵/₈* ⁴/₃=-2 ¹/₂ =-2,5
2)1 ²/₃ : (-3 ¹/₃)=⁵/₃*(-³/₁₀)=-½=-0,5
