Correct. Use the Change of Base formula with either common or natural logarithms:

$\displaystyle{\log}_{{{4}}}{40}=\frac{{{\log{{40}}}}}{{{\log{{4}}}}}\usepackage{cmbright}\Huge\$

Use the calculator to evaluate the quotient: $\displaystyle\frac{{{\log{{40}}}}}{{{\log{{4}}}}}=\frac{{{1.60205}...}}{{{0.60205}...}}={2.66096}...\usepackage{cmbright}\Huge\$

Round your answer to the nearest thousandth: 2.661