Answer:
The fundamental frequency is 159 Hz.
Explanation:
Given that,
First frequency = 1113 Hz
Second frequency = 1431 Hz
Third frequency = 1590 Hz
Here, three frequencies are separated from each other by the multiple of 159
We need to calculate the fundamental frequency
[tex]1113+159+159=1431\ Hz[/tex]
[tex]1431+159=1590\ Hz[/tex]
As, [tex]\dfrac{1113}{159}=7[/tex]
1113 Hz is the seventh harmonic of 159.
Hence, The fundamental frequency is 159 Hz.