I use Microsoft Office 2010 in Windows 10. Go to All Apps, Microsoft Office Folder if that is how you organized Office, Microsoft Office Picture Manager, Select a Photo, Select "Picture" on the header bar, a drop down menu appears, select compress, there are three size compression options, you can select each one to see the expected file size. They are labeled documents, web pages, and email messages. These size and compress options are also available from an Edit Pictures tab along the top of the panel.
This is not what I would have wanted as a method to compress a photo out of Windows 10 if I had a choice. Ridiculous to have to take a side trip to Office to compress or resize a photo in my opinion. Hope this helps.
Later Ed