6 целых 3/4 : 9 + 24 : 6/7 - 1/9 : 4 /21 / 53 целых 2/3 -22 целых 14/15 : 2 целых 2/3

$\frac{6 \frac{3}{4}:9+24: \frac{6}{7}- \frac{1}{9} : \frac{4}{21} }{53 \frac{2}{3}-22 \frac{14}{15} :2 \frac{2}{3} } = \frac{52}{85}$

1) 6 3/4:9=27/4 * 1/9=3/4
2) 24:6/7=24 * 7/6=28
3) 1/9:4/21=1/9 * 21/4=7/12
4) 3/4+28 - 7/12=28 9/12 - 7/12=28 2/12=28 1/6
5) 22 14/15:2 2/3=345/15 * 3/8=69/8=8 5/8
6) 53 2/3 - 8 5/8=53 16/24 - 8 15/24=45 1/24
7) 28 1/6 : 45 1/24=169/6 * 24/1105=52/85