You'll have to furnish a manufacturer and model number before the serial number means anything.
How old is a Kranich & Bach piano with serial number 65053?
How old is this piano with serial number 1510355
That is the model number not the serial number.
how old is my baldwin keyboard serial number 91002/28
how old is a Winchester 101 with a serial number of k236347
No serial number was provided.
No serial number provided.
No serial number = no way to answer
without a serial number I cannot say how old it is.
No way to tell from a serial number only.
Impossible to answer without knowing make or serial number.
how old is a Regent Flute serial number 9440