Владлен Третьяков 1) (-2 5/9 + 1 20/21) : 1 8/49 - 1 7/9 : (-6)=(-1 5/9 + 20/21) * 49/57 + 16/9 * 1/6= (-14/9 + 20/21) * 49/57 + 8/27=(-98+60)/63 * 49/57 + 8/27 = -38/63 * 49/57 + 8/27= -2/9 * 7/3 + 8/27 = -14/27+8/27=-6/27=-2/9;; 2) (5 5/9 - 6,8) : (2 13/30 - 2 1/12) *3,6=(5 5/9 - 6 4/5) : (13/30 - 1/12) * 18/5= (-1 4/5 + 5/9) : (26-5)/60 * 18/5=(-9/5+5/9) * 60/21 * 18/5=(-9/5+5/9) * 12/7 * 6/1= (-81+25)/45 * 72/7=-56/45 * 72/7=-8/5 * 8/1=-64/5=-12 4/5.
