You are using tuning forks to tune a stringed instrument. You can tune your instrument either to C (middle C is 256 Hz) or to A (high A is 440 Hz, and middle C is 262 Hz). When you play your untuned string with a C-256 tuning fork you hear 12 beats per second. When you play your untuned string with a C-262 tuning fork you hear 6 beats per second. What is the frequency of sound being produced by your stringed instrument?

Hz