Fixed Image Size

This is my blog. I am using the Equilibrium theme and the image dimensions are fixed for both the Featured and latest post section. The dimensions of Featured images are: Width 303px – Height 231px. The dimensions of Latest Post images are: Width 162px – Height 118px. I am currently resizing each and every image but I was wondering if there is a way to auto-resize the images to fit these dimensions. Thank you,