A spin-echo imaging sequence produces an image with a SNR=90 for muscle tissue when Nex=2. What SNR is expected when Nex=3?

SNR ∝ Nex1/2

(SNR)1/(SNR)2 = [Nex1/Nex2]1/2

90/(SNR)2 = [2/3]1/2

(SNR)2 = 110