Is this a doppler effect problem?

[cheez]

You hear something slitering toward you in the dark. You know from past experience that somethings slither with a frewuency of 130 Hz. If you hear a frequency of 130+17 Hz, how fast is the litherer slithering toward you (in m/s)? The speed of sound is 300 m/s


Is is a doppler effect problem? But there is no wavelength given in here? Can anybody tell me how to do it?

 

[Galileo]

Use the relation between wavelength, frequency and velocity to find the wavelength: $v=\lambda f$.
It's very easy to remember this formula, since f=1/T with T the period. The wave will travel 1 wavelength in 1 period, so v=wavelength/period.