The basic relationship between frequency, speed and wavelength of a wave is given by:
[tex]f= \frac{v}{\lambda} [/tex]
where
f is the frequency
v is the speed
[tex]\lambda[/tex] is the wavelength
The wave on the string in our problem has a speed of v=24.0 m/s and its wavelength is [tex]\lambda=0.300 m[/tex], so its frequency is
[tex]f= \frac{24.0 m/s}{0.300 m}=80 Hz [/tex]
