1.
a+b+c=180
a=3b
a=c-40 => c=a+40=3b+40
3b+b+3b+40=180
7b=140 => b=20
a=3b => a=60
c=100
2.
În prima zi - 2x/7 => rest 5x/7
A doua zi - 13/25 • 5x/7 + 379
A treia zi - 2561
2x/7 + 13x/35 + 379 + 2561 = x
2x/7 + 13x/35 + 2940 = x
35x-10x-13x=2940•35
12x=2940•35
x=245•35
x=8575 kg