a + b = 343
b + c = 297
a + c = 360
~
a, b, c = ?
~
a + b + b + c + a + c = 343 + 297 + 360
2a + 2b + 2c = 1000
2 · (a + b + c) = 1000 /:2
a + b + c = 500
343 + c = 500 /-343
c = 157
a + c = 360
a + 157 = 360 /-157
a = 203
a + b = 343
203 + b = 343 /-203
b = 140
/robertinni