I can’t figure out the 2 digit number after 7 tries, how do I do it?

Hint: Start with 50 to find out if it is higher or lower, then continue to narrow it down by half the remaining choices until you get close. If you do not get the correct number the first time you can try again.

Check the walkthrough for more help with this game

https://www.appgamer.com/an-elmwood-trail-crime-story/episode-3-walkthrough