The maximum displayed image width for Pilcrow is found here:
The images must be presized prior to uploading so they do fit into a single line within the width allowing some spacing between them. As you the images to be side by side on the same line start by setting the alignment to left. http://en.support.wordpress.com/images/image-alignment/#side-by-side
See here please > http://en.support.wordpress.com/visual-editor/#alignment
The alignment icons in the WordPress editor are for aligning text; they are not for aligning images. They are used to achieve wrapping text around images on either the right or left hand side, or to display an image that's centered without text on either side of it.
Align-left means position left, with the rest of the content wrapping around the right side of the image.
Align-right means position right, with the rest of the content wrapping around the left side of the image.
Align-center means position center, with no wrap-around (= the rest of the content below the image).
If the text beside the images does not occupy the same amount of space that the image beside it does then the text wrapping will continue and the images and text that follow will have a staggered appearance.
To prevent the staggered effect what you do is insert the following snippet of code into the Text (HTML) editor after each image/text pair: