Question

Intr-o ferma de pasari sunt 425 de rate si gaste, 297 de gaste si curci si 210 rate si curci.Cate pasari sunt de fiecare fel?

Answer 1

r + g = 425
g + c = 297
r + c = 210
_____________ adunam toate ecuatiile
2r + 2g + 2c = 932  / : 2
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r + g + c = 466 pasari in total
r + g = 425
______________ scadem ecuatiile
/ + / + c = 41 de curci
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r + g + c = 466 pasari in total
g + c = 297_________ scadem ecuatiile
r + / + / = 169 de rate
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r + g + c = 466 pasari in total
r + c = 210
_____________ scadem ecuatiile
/ + g + / = 256 de gaste