What Is the Vibrational Frequency of a Guitar String Based on Beat Frequencies?

[Malicious]

Homework Statement

A guitar string produces 4 beat/s when sounded with a 350-Hz tuning fork and 9 beat/s when sounded with a 355-Hz fork. What is the vibrational frequency of the string? Explain your reasoning.

Homework Equations

f=v//\

The Attempt at a Solution

I'm not quite sure how to start solving this problem. I know that frequency is velocity divided by wavelength. What equation or equations that have beat/s as variables could I use to solve this problem?

 

[andrevdh]

http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html"

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