Odpowiedź:
(12g + 4)/2 - (10g - 1)/5 =[5(12g + 4) - 2(10g - 1)]/10 =
= (60g + 20 - 20g + 2)/10 = (40g + 22)/10 = 2(20g + 11)/10 =
= (20g + 11)/5
