Question

Найдите неизвестный член пропорции:

х:8/9 = 3:4

х:2.8 = 3:4

12:7 = 9:х

6.5:5.2 = х:8

4.5:3.6 = х:4

15:4 = х: 1 1/3 (в конце однерка типо целое число в дроби)

Answer 1

$\frac{9x}{8} = \frac{3}{4}$

$36x=24$ $18x=12$ $9x=6$ $3x=2$

$x=\frac{2}{3}$

$\frac{x}{2.8} = \frac{3}{4}$

$4x=2.8*3$

$4x=8.4$

$x=\frac{8.4}{4} = 2.1$

$\frac{12}{7} =\frac{9}{x}$

$12x=7*9$

$12x=63$

$x= \frac{63}{12} =5.25$

$\frac{6.5}{5.2}= \frac{x}{8}$

$5.2x=8*6.5$

$5.2x=52$

$x=\frac{52}{5.2} = 10$

$\frac{4.5}{3.6} = \frac{x}{4}$

$3.6x=4.5*4$

$3.6x=18$

$x=\frac{18}{3.6} = 5$

$\frac{15}{4} = \frac{3x}{4}$

$3x=\frac{15*4}{4}$

$3x=15$

$x=\frac{15}{3} = 5$