If it is 226 x 318 pixels, it is 72 PPI. Check it in PhotoPaint Resample Dialog.
226 x 318 pixels, it's 72 dpi if the image size is 7,97x11,22 cm
If the image size is 1,91 cm x 2,69 cm you have the same image at 300 dpi. You can go to the Image menu in PhotoPaint, Resample, and ckeck the "Maintain original size" box. But it's the same image, smaller or greater. Same content, same quality, same results. Is like a to enlarge a bitmap manually on CorelDRAW, the resolution decreases when size increases....
The file size (in Kb) however, also depends on other factors, like the Compression ratio when save, and the Color Mode, for example
Lead Technologies, inc is the creator of LeadTools, witch is part of Microsoft Expression