Răspuns:
7) a+b+c=127
b=2a+0,5=>a=(b-0,5)/2
b=c-1=>c=b+1
(b-0,5)/2+²⁾b+²⁾b+²⁾1=²⁾127
b-0,5+2b+2b+2=254
5b=254+0,5-2=>b=252,5:5=>b=50,5 lei are al2lea copil
a=(50,5-0,5):2=>a=25 lei are primul copil
c=50,5+1=51,5 lei are al3lea copil
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10) (a+b+c)/3=20
a+b+c=20·3
a+b+c=60
b=2a+6
a=c+10=>c=a-10
a+2a+6+a-10=60
4a=60-6+10
a=64:4=>a=16
b=16·2+6=>b=38
c=16-10=>c=6
