Two tuning forks, 254 Hz. and 260. Hz, are stuck simultaneously. how many beats will be heard?

When the vibrations of both forks 'mix', new sum - and difference-

frequencies are generated.

The beat at (260 - 254) = 6 Hz is easy to hear, because it causes

the original two sounds to waver in a rapid 'wah-wah-wah' fading

pattern at 6 times a second.

The sum product at (254 + 260) = 514 Hz is harder to hear, with

everything else that's going on. But it's there.