Maybe use your brain and not ask the internet for the answer to all your easy math problems.
Let \(w\) equal number of miles Martha walked
\(\frac{2.9mi}{1hr}=\frac{w}{0.57hrs}\)
\(1hr\times w=0.57hrs\times2.9mi\)
\(1hr\times w= 1.653mi/hr\)
\(w=1.653mi\)
Martha walked for 1.653 miles.