Question

an organ pipe open at both ends vibrate with a frequency n which is its pth overtone when one end of the pipe is closed it vibrates with a frequency N which is its qth overtone

Answer 1

an organ pipe open at both ends vibrate with a frequency n which is its pth overtone when one end of the pipe is closed, it vibrates with frequency n which is its qth overtone show that 
N=(2q1)n\2(p1)