If a rod of length 250cm is measured as 255cm long in error, what is the percentage error in the measurement?

If \((\frac{2}{3})^{m} (\frac{3}{4})^{n} = \frac{256}{729}\), find the values of m and n.

Without using tables find the numerical value of log\(_7\)49 + log\(_7\)(\(\frac{1}{7}\))

Factorize completely 81a\(^4\) - 16b\(^4\)