This figure you are seeing for resolution is only for printing purposes, where you would almost certainly want to change it. The actual resolution of your camera image is w x h pixcels. A quick look at one of mine shows 4288 x 2848 pixcels.
So if I was to print that on a sheet of A4, in landscape mode and borderless, I would be printing at a resolution of approximately 350 pixcels ( or dots) per inch. If I printed it at 72 dpi I would have a picture approximately 60 x 39 inches !
To put it another way, at the 350 dpi level I would have quite a nice glossy image, at 72 dpi it would be much larger but the quality would only be about that of a photo in a newspaper. Cropping an image reduces the size of the image but it doesn't itself change the resolution.