531.
х-2 7/12=5 3/18
х=5 3/18+2 712
х=7 27/36= 7 3/4
х-3717/54=15 16/45
х=15 16/45+37 17/54
х=52 181/270
х-26 7/21=100 5/28
х=100 5/28+26 7/21
х=126 36/84= 126 3/7
х-33 21/25=42 17/35
х=42 17/35+33 21/25
х= 75 232/175=76 57/175
537.
4 11/45+(3 14/15+5 2/45)=(4 11/45+5 2/45)+3 14/15=9 13/45+3 14/15= 12 55/45= 12 11/9
44 8/70+(46 18/35+2 9/70)=(44 8/70+2 9/70)+46 18/35=46 17/70+46 18/35=
92 53/70
7 43/50+(2 31/50+4 17/25)=(7 43/50+2 31/50)+4 17/25=9 74/50+4 17/25=
13 108/50= 13 54/25= 14 29/25
55 19/72+(19 5/24+20 17/72)=(55 19/72+20 17/72)+19 5/24=75 36/72+19 5/24= 94 51/72= 94 17/24
538.
3 161/175+(53 13/25+18 34/35)=3 161/175+71 261/175=74 422/175= 76 72/175
9 21/25+(30 4/15+18 64/75)=(9 21/25+30 4/15)+18 64/75=39 83/75+ 18 64/75=57 147/175
78 37/48+(39 23/24+14 15/16)=78 37/48+53 91/48=131 128/48= 131 8/3=
133 2/3
304 59/80+(99 21/40+14 127/160)=304 59/80+113 211/160=417 329/160=
419 9/160