[tex] {( {4}^{2} \div {3}^{2} )}^{2} \times {4}^{18} \div {256}^{5} = {( {4}^{2} \div {3}^{2} ) }^{2} \times {4}^{18} \div {4}^{20} = \frac{ {( {4}^{2} \div {3}^{2} ) }^{2} \times {4}^{18} }{ {4}^{20} } = \frac{ {( \frac{ {4}^{2} }{ {3}^{2} }) }^{2} }{ {4}^{2} } = \frac{ \frac{ {4}^{4} }{ {3}^{4} } }{ {4}^{2} } = \frac{ {4}^{4} }{ {3}^{4} } \div {4}^{2} = \frac{ {4}^{4} }{ {3}^{4} } \times \frac{1}{ {4}^{2} } = \frac{ {4}^{2} }{ {3}^{4} } = \frac{16}{81} [/tex]
