Răspuns:
Explicație pas cu pas:
2/31 + 2/30 + 2/29 = x·2/28 <=>
2( 1/31 + 1/30 + 1/29) = 2·(x/28) =>
³⁰ˣ²⁹ˣ¹⁴⁾1/31 + ³¹ˣ²⁹ˣ¹⁴1/30 + ³¹ˣ³⁰ˣ¹⁴1/29 = ³¹ˣ¹⁵ˣ²⁹x/28
Numitor comun = 31·30·29·14 = 377580
12180+12586+13020= 13485·x =>
37786 = 13485·x =>
x = 37786/13485