Ответ:
Пошаговое объяснение:
x : 8 = 4 : 2
2*x = 8*4
2x = 32
x = 32 : 2
x = 16
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7,8 : x = 7,2 : 1,2
7,2*x = 7,8*1,2
7,2x = 9,36
x = 9,36 : 7,2
x = 1,3
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2 2/7 : 1 1/7 = x : 2 1/9
1 1/7 * x = 2 2/7 * 2 1/9
8/7x = 16/7 * 19/9
8/7x = 304/63
x = 304/63 * 7/8
x = 38/9
x = 4 2/9
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5 : 4 = 2,5 : x
5*x = 2,5*4
5x = 10
x = 10 : 5
x = 2