Fractions .... While still involved in the building/remodeling industry, you would be surprised (perhaps not) how Millennials through Gen X ... that could NOT fathom fractions. My lead carpenter took on three apprentices, one was his nephew, one his son, and one was ?. None of them could add, even when given a pencil and paper, 22' 1 and 1/16" and 10' 3/8".
I kid you not, that's an actual example. All three of them couldn't quite get it. I only know about this one, as I witnessed such. In any event, the lead was a union journeyman, and said it was the same with even any of the younger (42 and younger) union apprentices. He was trying to explain and was becoming so frustrated that I thought he was going to put one of their heads under my Makita slider (I was running crown for that house). So, I stepped in and told him to just relax and I'd handle it.
So, I asked them ... What does 22 plus 10 equal? One of them actually went to the calculator on their phone ... I started laughing so hard that I spit out the sip of coffee I had just taken. When I got them all to agree that the answer was 32 feet, I moved on to the one inch. That's when the party started ... the two simple fractions.
I then asked them how many sixteenths were in an eighth. Not one of the three knew. Two had college degrees. So, I tried to explain to them ... There are two 64ths in a 32nd. There are two 32nds in a sixteenth. Two sixteenths to an eighth. Two eighths to a quarter. And, two quarters to a half.
So, in the second measurement, there's how many sixteenths? No answer. So ... REMEMBER? Two sixteenths to an eighth. So, how many sixteenths are there with the 3/8? Again, no answer. Then I asked, what does two times three equal? This time the calculator boy (yes, he pulled out his phone) answered correctly, SIX he said.
So, 1/16 plus 3/8 equals what?
I walked over to one of my bags, pulled out a framing hammer (Big Blue 28 oz), walked over to my lead and asked him, "Do you want to use this? Or, can I?"
And .... THEY VOTE!