Răspuns:
Explicație pas cu pas:
a)
0,(3) = 3/9 = 1/3
0,(6) = 6/9 = 2/3
x/(1/3) = k sau 3x = k sau x = k/3
y/(1/4) = k sau 4y = k sau y = k/4
z/(2/3) = k sau 3z/2 = k sau z = 2k/3
2x + 3y - z = 66
2k/3 + 3k/4 - 2k/3 = 66
3k/4 = 66
k= 4*66/3 = 88
x = 88/3 m
y = 88/4 = 22 m
z = 2*88/3 = 176/3 m
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b)
P = x + y + z = 88/3 + 22 + 176/3 = 264/3 + 22 = 88 + 22 = 110 m
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c)
35% mamifere
20% insecte
pasari = 100% - (35% + 20%) = 100% - 55% = 45%
35*100/20 = 175% (mamifere in raport cu insectele)
pasari = 63
63*100/45 = 140 exponate
20*140/100 = 28 insecte
