1)2целых1/7:2,5=8,4:7х 2)4,5х:2,7=9:1,8

$2 \frac{1}{7} : 2,5 = 8,4 : 7x$

$\frac{15}{7} : \frac{25}{10} = 8.4 : 7x$

$\frac{6}{7} = 8.4 : 7x$

$7x = \frac{84}{10} : \frac{6}{7}$

$7x = \frac{7}{5} * 7$

$7x = \frac{49}{5}$

$x = \frac{49}{5} : 7$

$x = \frac{7}{5} = 1 \frac{2}{5} = 1.4$
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$4.5x : 2.7 = 9 : 1.8$

$\frac{4.5x}{2.7} = \frac{9}{1.8}$

$4.5x * 1.8 = 2.7 * 9$

$4.5 * 1.8 = 24.3$

$4.5x = 24.3 : 1.8$

$4.5x = 13.5$

$x = 13.5 : 4.5$

$x=3$
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