The length of an open pipe and a closed pipe are in ratio 3:2. The ratio of the third overtone of closed pipe and the second overtone of open pipe is?

Dear student,
let length of open pipe=l1=3x and closed pipe =l2=2x
velocity of sound= v
3rd overtone of closed pipe= (7v)/(4l2)
2nd overtone of open pipe= (3v)/(2l1)
Ratio= (7v/4l2)/(3v/2l1)
Putting values of l1 and l2 and solving we get,
Required ratio= 7 : 4 [Ans]
Hope it helps.
Thanks;
Soumya Ranjan Mohanty.