Question

x/3=8/12 B) 2/x=14/21 c) 1/6=5/x d) 2/6=3/x

Answer 1

É só fazer uma regra de 3, esse foi o melhor jeito que achei

Answer 2

$\dfrac {x}{3} = \dfrac {8}{12} \\\\ 12.x = 8.3 \\\\ 12x = 24 \\\\ x = \dfrac {24}{12} \\\\ x = 2$

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$\dfrac {2}{x} = \dfrac {14}{21} \\\\ 14.x = 2.21 \\\\ 14x = 42 \\\\ x = \dfrac {42}{14} \\\\ x = 3$

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$\dfrac {1}{6} = \dfrac {5}{x} \\\\ 1.x =5.6 \\\ 1x = 30 \\\ x = 30$

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$\dfrac {2}{6} = \dfrac {3}{x} \\\\ 2.x = 3.6 \\\\ 2x = 18 \\\\ x = \dfrac {18}2} \\\\ x = 9$