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3 years ago

Trei copii au impreuna 45 de lei .

Mathematics

1 answer:

Ainat [17]3 years ago

7 0

Answer:

Primul copil are 6 lei, al doilea are 12 lei, al treilea are 27 de lei.

Step-by-step explanation:

Lăsați suma primului copil să fie x.

Lăsați suma al doilea copil să fie y.

Lăsați suma al treilea copil să fie z.

Trei dintre ei au 45 de lei în total.

Aceasta înseamnă că:

x + y + z = 45 ________(1)

Al doilea are de două ori valoarea primului:

y = 2x

Al treilea are cu 15 lei mai mult decât al doilea:

z = 15 + y

=> z = 15 + 2x

Puneți valoarea y și z în (1):

x + 2x + 15 + 2x = 45

5x = 45 - 15 = 30

x = 30 / 5 = 6 lei

=> y = 2 * 6 = 12 lei

=> z = 15 + 12 = 27 lei

Primul copil are 6 lei, al doilea are 12 lei, al treilea are 27 de lei.

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