I+M+A=165 kg
I = M+M:2 /×2
2I=2M+M
2I=3M ==>I =3M/2
M = A+A:4 /×4
4M=4A+A
4M=5A ==> A=4M/5
inlocuim in prima ecuatie in functie de M
3M/2+M+4M/5 = 165 /×10
15M+10M+8M=1650
33M= 1650
M = 1650 : 33
M = 50 kg (Macinat)
A=4×50/5 = 4×10= 40 kg (Ana)
I = 3×50/2= 3×25= 75 kg (Ioana)
Verificare:
50+40+75= 165 kg
Succes!