8,5-5/8*2,4/(7/15-5/18)*2 11/17=(2 3/22-2/55)*0,6/0,45х

Решаем пример по деяньям:

1) 7/15 - 5/18 = 6 * 7/90 - 5 * 5/90 = (42 - 25)/90 = 17/90;

2) 17/90 * 2 11/17 = 17/90 * (2 * 17 + 11)/17 = 17/90 * 45/17 = (17 * 45)/(90 * 17) = 1/2;

3) 5/8 * 2,4/(1/2) = 5/8 * 24/10 * 2 = (5 * 24 * 2)/(8 * 10) = 3;

4) 8,5 - 3 = 5,5;

5) 2 3/22 - 2/55 = 47/22 - 2/55 = 5 * 47/110 - 2 * 2/110 = (235 - 4)/110 = 231/110 = 21/10;

6) 21/10 * 0,6 = 21/10 * 3/5 = 63/50;

7) 5,5 = 63/50 : (0,45 * х);

0,45 * х = 63/50 : 55/10 = 63/50 * 10/55 = (63 * 10)/(50 * 55) = 63/275;

х = 63/275 : 45/100 = 63/275 * 100/45 = (63 * 100)/(275 * 45) = (7 * 4)/(11 * 5) = 28/55;

Ответ: х = 28/55.