Just letting you know, I'm in Stats class in college and I have to refresh myself on all of this stuff. You have no idea how appreciative I am for you to explain it this way. Seeing you square out each section really opened me up to a different type of learning. Man I appreciate you so much, thank you!
Honestly, it would guarantee that you've landed on the middle value, so it's a smart move! But most (non-evil) instructors will have enough wiggle room that simply looking for 50%*n or 25%*n will land you in the correct interval for the median or Q1.
This is why finding median on a histogram is a bit silly. We can't write the actual value. Most professors would want you to write that the median falls in the interval [6, 8) as we have no idea where in that interval the median lies.
