Răspuns:
6 zile
Explicație pas cu pas:
12 muncitori ............... 5 zile
10 muncitori ............... x zile (invers proportional)
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x = 12·5/10 = 60/10 = 6 zile
I 1/2 - 2/3 I + I 2/3 - 3/4 I = ?
Comparam numerele din fiecare modul:
³⁾1/2 si ²⁾2/3 <=> 3/6 si 4/6 => 4/6 > 3/6 =>
I 1/2 - 2/3 I = 2/3 - 1/2
⁴⁾2/3 si ³⁾3/4 <=> 8/12 si 9/12 => 9/12 > 8/12 =>
I 2/3 - 3/4 I = 3/4 - 2/3 =>
I 1/2 - 2/3 I + I 2/3 - 3/4 I = 2/3 - 1/2 + 3/4 - 2/3 =
= 3/4 - ²⁾1/2 = (3-2)/4 = 1/4
