Question

A=(\frac{1}{2})^{-4}+(\frac{1}{3})^{-3} +(\frac{4}{5})^{-1} - ( \frac{2}{7})^{-2}

Answer 1

$A=(\frac{1}{2})^{-4}+(\frac{1}{3})^{-3} +(\frac{4}{5})^{-1} - ( \frac{2}{7})^{-2}\\=2^4+3^3+ \frac{5}{4} - \frac{7^2}{2^2} =16+9+ \frac{5}{4} - \frac{49}{4}=\\ \frac{64}{4} + \frac{36}{4}+ \frac{5}{4} - \frac{49}{4}= \frac{56}{4} = 14$

A = 14

Saludos!