1)a-b=308
a:b=8 rest 35
a=8b+35
8b+35-b=308
7b=308-35
7b=273
b=39
a=8*39+35= 312+35=347
2)a)(5y+7):24=13
(5y+7)=24*13
5y+7=312
5y=312-7
5y=305
y=61
b)236:(7z-3)=59
7z-3=236:59
7z-3=4
7z=4+3
7z=7
z=1
3)(a+a+1+a+2):7=24 rest 6
3a+3=7*24+6
3a+3=168+6
3a=168+6-3
3a=168+3
3a=171
a=57
a+1=57+1=58
a+2=57+2=59