To get exact proportions stated, you would have to uncheck the Constrain Proportions. This should not be done on all types of images. You wouldn't want to do this on a photo of someone (unless you didn't like them). You can either change the width from 490w to 100w making the height 143h or change the height from 700h to 200h making the width 140w.

100w x 143h
or
140w x 200h