Question

3,8:19=x:30,7:0,9=14:y​

Answer 1

3,8 : 19 = х : 3 - это пропорция

19 · х = 3,8 · 3 - свойство пропорции

19 · х = 11,4

х = 11,4 : 19

х = 0,6

Проверка:

3,8 : 19 = 0,6 : 3 = 0,2 - верно.

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0,7 : 0,9 = 14 : у - это пропорция

0,7 · у = 0,9 · 14 - свойство пропорции

0,7 · у = 12,6

у = 12,6 : 0,7

у = 18

Проверка:

0,7 : 0,9 = 14 : 18 = 0,(7) - верно.

Answer 2

To solve for x and y in the given equations:

1. 3/8 = x/30 Cross-multiply to solve for x: 3 * 30 = 8 * x 90 = 8x

   Divide both sides by 8 to isolate x: x = 90 / 8 x = 11.25

2. 7/0.9 = 14/y Divide both sides by 7 to solve for 1/y: 1/y = (14 / 0.9) / 7

   Now, find the value of 1/y: 1/y = (14 / 0.9) / 7 ≈ 21.1111

   To solve for y, take the reciprocal of 1/y: y = 1 / (1/y) y ≈ 1 / 21.1111 y ≈ 0.0476 (rounded to four decimal places)

So, the solutions are: x ≈ 11.25 y ≈ 0.0476