A rare thing, an actual application for math in real life

This past Sunday i had to build some stairs for the front of my house. i had a rise of 18 in and a run of 29 for the riser. i needed the angles in top and bottom so i remembered that old trig class with Jackson, ans used the inverse tan. after having the angles the hard way i obtained an excessively large protractor and in the end cut the boards to near precision. my mom was off by 5-6 deg on her drawing (carpenter classes teach you to shortcut and be lazy) but mine were good to 4 decimal places. after she quit due to being outsmarted by a high schooler, i made some mathematically perfect stairs.