16 : (0,3 * x +2,5) : x = 17 + 3= 20
-> \(\frac{0,3\times x+2,5}{x}=\frac{16}{20}=\frac{4}{5}\)
\(\frac{0,3\times x}{x}+\frac{2,5}{x}=\frac{4}{5}\)
\(0,3+\frac{2,5}{x}=\frac{4}{5}\)
\(\frac{2,5}{x}=\frac{4}{5}-0,3\)
\(\frac{2,5}{x}=\frac{1}{2}\)
\(x=2,5:\frac{1}{2}=5\)
Mình thay x là a nha:
16 : (0,3 x a + 2,5) : a - 3 = 17
(16 : 0,3 x 16 :a + 26 : 2,5) : a = 17 + 3
(\(\frac{160}{3}\) x \(\frac{16}{a}\) + \(\frac{52}{5}\)) : a = 20
\(\frac{160}{3}\) : a x \(\frac{16}{a}\) :a + \(\frac{52}{5}:a\)= 20
\(\frac{160}{3a}\times\frac{16}{a\times a}+\frac{52}{5a}=20\)
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