Corel draw file opening

I’m going be putting Corel draw X4 or X6 back on my computer 

but my friend who has done files some posters and text on A4 paperwork 

but he has used Corel draw 10 

can Corel draw x4 or x6 open the Corel draw 10 files ok so no issues as need to be able to open the Corel draw 10 files 

thanks