Question

avand cate 5000 lei, Maria si Elena au plecat la cumparaturi.Aflati cati lei a cheltuit fiecare, daca resturile sunt numere consecutive, care valoreaza la un loc cat suma cheltuita de Elena.

Answer 1

x=a cheltuit Elena, i-a ramax 5000-x
y=a cheltuit Maria, i-a ramas 5000-y
5000-x=5000-y+1
5000-x+5000-y+1 = x
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y-x=1
-y-2x = -10000, si le adun
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-3x = -9999 I *(-1)
x=3333
y=x+1= 3334
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Verificare: 5000-3333=1667 si 5000-3334=1666, deci numere consecutive si 
1667+1666 = 3333, cat a cheltuit Elena, OK.