Răspuns :
a + b + c = 9 000
a + b = 6 000
b + c = 7 500
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9 000 - 7 500 = 1 500 ( a ) → primul numar
6 000 - 1 500 = 4 500 ( b ) → al doilea numar
7 500 - 4 500 = 3 000 ( c ) → al treilea numar
a+b+c=9000
a+b=6000
b+c=7500
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a,b,c=?
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a+b+c=9000
6000+c=9000
c=9000-6000
c=3000
b+c=7500 ⇒b+3000=7500⇒b=7500-3000⇒b=4500
a+b=6000⇒a=6000-4500⇒a=1500
VERIFICARE : a+b+c=1500+4500+3000= 6000+3000=9000