Answer:
F = 268 Hz
Step-by-step explanation:
The beat frequency is given as:
|
So, for the first flute and tuning fork:

where,
F = Frequency of tuning fork
F = 248 Hz ± 20 Hz
F = 268 Hz (OR) 228 Hz
Now, for the second flute and tuning fork:

where,
F = Frequency of tuning fork
F = 288 Hz ± 20 Hz
F = 268 Hz (OR) 308 Hz
Since, 268 Hz is common from both calculations. Therefore, it will be the frequency of the tuning fork.
F = 268 Hz