Question

preciso de calculos...

Answer 1

3)
$\frac{10}{x} = \frac{7}{14}$
7x = 140
x = 140/7
x = 20

$\frac{10}{8} = \frac{7}{y}$
10y = 7.8
y = 56/10
y = 5,6

x + y = 20 + 5,6 = 25,6

4)
$\frac{12}{4} = \frac{9}{y}$
12y = 9.4
y = 36/12
y = 3

$\frac{12}{4} = \frac{x}{1,5}$
4x = 12.1,5
x = 18/4
x = 4,5

x - y = 4,5 - 3 = 1,5

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