Х/5 = 3/8
8х = 5*3
8х = 15
х = 15/8
х = 1 7/8
х=1,875
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1,875 /5 = 3/8
15/8 : 5 = 3/8
15/8 * 1/5 = 3/8
3/8 = 3/8
5/х=3/b
3x = 5b
x= 5b/3
x = 1 2/3 * b
5x =1/2
x = 1/2 : 5 = 1/2 * 1/5 = 1/10
х = 0,1
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5 * 0,1 = 1/2
0,5 = 1/2
5/10 = 1/2
1/2 = 1/2
3/х = 1 : 1/2
3/х = 1 * (2/1)
3/х = 2/1
2х = 3*1
х = 3/2
х = 1,5
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3/1,5 = 1 : 1/2
2 = 2