You are downloading the Youth Math AppX file v18.104.22.168 for Windows Phone. Youth Math is a free and fun Family game: Youth Math is a timed math application. Youth Math allows you to select which of the four (addition, subtraction, division, and multiplication) ... You can now download the offline AppX file to install & try it.
Download Locations for Youth Math 22.214.171.124 AppX file
Note: To install it manually from an SD card, you should choose one of the server location above to get the offline Youth Math AppX file, move the file to your phone's SD card and then tap 'Install local apps' in the phone's App list.