Ответ:
а) \(\left(\frac23:\frac49\right)^2=\left(\frac23\cdot\frac94\right)^2=\left(\frac32\right)^2=\frac94=2\frac14\).
б) \(\left(\frac23\right)^2:\left(\frac49\right)^2=\frac49:\frac{16}{81}=\frac49\cdot\frac{81}{16}=\frac94=2\frac14\).
в) \(\left(\frac29:\frac78:\frac7{18}\right)^3=\left(\frac29\cdot\frac87\cdot\frac{18}7\right)^3=\left(\frac{16}{49}\right)^3=\frac{4096}{117649}\).
Ответ: а) \(2\frac14\); б) \(2\frac14\); в) \(\frac{4096}{117649}\).
