Salut.
a + b = 459
a - b = 63 => a = b + 63
b + 63 + b = 459
2b + 63 = 459
2b = 459 - 63
2b = 396
b = 396 ÷ 2
[tex]\boxed{b=198}[/tex]
a = 198 + 63
[tex]\boxed{a=261}[/tex]
c + d = 186 tone
c - 60% din c = 12 × (d - 5/6 din d)
100c/100 - 60c/100 = 12 × (6d/6 - 5d/6)
40c/100 = 12 × d/6
4c/10 = 12d/6
2c/5 = 2d => 2d = 2c/5
d = 2c/5 ÷ 2
d = 2c/5 × 1/2
d = 2c/10
d = c/5
c + c/5 = 186
5c + c = 930
6c = 930
c = 930 ÷ 6
[tex]\boxed{c=155}[/tex] tone
d = 186 - c
d = 186 - 155
[tex]\boxed{d=31}[/tex] tone
- Lumberjack25