Respostas

2014-05-20T19:28:32-03:00
300___100%
21____X
x= 21x100/300
x=2100/300
x= 7%
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450___100%
X ____8%

x= 450x8/100
x=3600/100
x= 36

450-36= 414
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A melhor resposta!
2014-05-20T19:35:40-03:00
300\cdot \frac{p}{100}=21

\frac{p}{100}= \frac{21}{300}

\frac{p}{100}=0,07

p=0,07 \cdot 100

p=7 \%

R: Equivale à 7% do total

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450\cdot \frac{8}{100}=x

450\cdot0,08=x

x=36

Valor do desconto: R$36

Está sendo vendida por: R$414

450-36=414

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