O doime din merele Alinei reprezinta o treime din merele lui Bogdan.Daca ei au impreuna 15 mere.Cate mere are fiecare? Front fracții

a/2 = b/3 ⇒ b=3a/2

a+b=15

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a + 3a/2 = 15

2a+3a=30

5a=30

a=30:5=6 mere are Alina

b=15-6=9 mere are Bogdan

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Verific: 6+9=15 mere in total si 6/2=3=9/3=3, corect.

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Metoda 2: a/2=b/3=k, a=2k si b=3k. a+b=2k+3k=5k=15, deci k=15:5=3 si de aici avem

a=2k=2*3=6 si b=3*k=3*3=9.