Demo 1

textpic (text/images) this image column  is resized to 25%. Then the text occupies the remaining space (75%)

Demo 2

content type text/media. the movie is resized to 33%. 

Demo 3

textpic (text/images) - the space hosting the images is resized to 66%.
The remaining space is assigned automatically to the text.
Columns: 2

Demo 4

This content is textmedia with imagebelow centered and resized to 50%. To do this select from Appereance tab, Layout > image/media size 50% and from Media tab below center

Demo 5

textpict content (text with images) - image colum is resized to 75% and put above, columns: 4

Dermo 6

On some cases you want to obtain the following output, where you put the image to the left (resized to 25%) without any text to the right. The trick is simple: insert a content typo3 like Text with Image and configure the size to 25% avoiding to insert the text. In this way you can get a single image aligned (right/left side) with the preferred witdh:

Demo 7

Following the previous example, here the image container is set to 66% of the column space available (100%). As you can see here, the output was set to 4 images (1 row), with the option "Beside text left";  if you select "Beside text, right" you obtain a different output with the images aligned to the right side.

Demo 8

Below there are 3 images, content type: Images Only - The image container is set to 66%, 3 columns