It would really help to know which Adobe product you are referring to. If you are talking about Lightroom, then this is how I would do it:
In the crop tool I would create a custom ratio of 10:76 and then crop the image. Then, in the export module I would set the export dimensions to the long side being 760 pixels and the export file type to JPEG. There are other ways to do it as well. This is only a suggestion.
If you are talking about a different program, please indicate.