Sometimes when I have typed in the page size in CorelDRAW I was doing two things at the same time. DRAW natively used inches in 10ths, but will take standard notation. For example: if your width was 3 3/4", you could type it in the Property bar just like that, and DRAW automatically changes that to 3.75". This works when specifying the measurement anywhere in DRAW you need to specify.

If you have resized your graphic and need the heighth and width to be independent of each other, then unlock the lock icon to the right of the x and y measurement spin buttons.

It is likely that there is some error here, or you have misread your ruler if you sized it from drawing guides.

Best to specify in the Property Bar for your sizes.

I have made all these mistakes when I am hurrying. I pays to measure twice so that the output is what you intended on when your were talking on the phone, answering your cell phone, checking your pager, checking if the scanner is warmed up. Attention is divided and things suffer for it.

Good luck.