Wind speed and doppler effect

Never would I have thought that wind has any effect on sound waves, but...
"The source of a sound wave is stationary. The observer is moving toward the source. There is a steady wind blowing from the observer to the source. How does the wind change the observed frequency?"

The answer is "The wind magnifies the doppler effect and increases the frequency."

I used the equation, Frequency of listener = freq. of source * (v sound + v listener / v sound )

So I guess the wind velocity would...

Wind speed and doppler effect