Two waves having the intensities in the ratio of 9;1 produce interference. The ratio of maximum to minimum intensity is equal to

Intensity ratio = =I1I2=91Amplitude ratio +=a1a2=31Ifa1=3 units, then a2=1 unit.   At maxima amax=a1+a2=4  At minima amin=a1−a2=2 ImaxImin=amax2amin2=164=41