Х×2 1/2: 1 1/5 -7/18=1 5/6

Х * 2 1/2 : 1 1/5 - 7/18 = 1 5/6;

Х * (2 * 2 + 1)/2 : (1 * 5 + 1)/5 - 7/18 = (1 * 6 + 5)/6;

Х * 5/2 : 6/5 - 7/18 = 11/6;

Х * 5/2 * 5/6 = 11/6 + 7/18;

Х * 25/12 = 33/18 + 7/18;

Х = (33 + 7)/18 * 12/25 = 40/18 * 12/25 = (40 * 12)/(18 * 25) = (8 * 2)/(3 * 5) = 16/15;

Ответ: х = 16/15.