a) \(\left(\frac{1}{3}x\right):\frac{2}{3}=\frac{7}{4}:\frac{2}{5}\)
\(\left(\frac{1}{3}x\right):\frac{2}{3}=\frac{35}{8}\)
\(\left(\frac{1}{3}x\right)=\frac{35}{12}\)
\(x=\frac{35}{4}\)
b) \(4,5:0,3=2,25:\left(0,1x\right)\)
\(15=2,25:\left(0,1x\right)\)
\(0,1x=\frac{3}{20}\)
\(x=1,5\)
c) \(8:\left(\frac{1}{4}x\right)=2:0,02\)
\(8:\left(\frac{1}{4}x\right)=100\)
\(\left(\frac{1}{4}x\right)=0,08\)
\(x=0,32\)
d) \(3:\frac{9}{4}=\frac{3}{4}:\left(6x\right)\)
\(\frac{4}{3}=\frac{3}{4}:\left(6x\right)\)
\(6x=\frac{9}{16}\)
\(x=\frac{3}{32}\)
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