You can't always use results to justify cause. Given the situation that most adults (even with higher education) are not good at math (possibly due to the failu

You can't always use results to justify cause. Given the situation that most adults (even with higher education) are not good at math (possibly due to the failure of education) -- in particular, most adults are infused with the perception that math is hard -- you will find them naturally trying to avoid math as much as they can. So you find that eighty percent of adult rarely ever use beyond Excel and 8th grade math. Can you use this result to go back and justify that we don't need math beyond 8th grade? I beg to differ. I only can provide anecdote. As myself are not bad at math, I find myself use calculus and linear algebra all the time. In fact, I think differently. As another anecdote, my son, who I consider is not nearly good at math, he is in middle school and he uses trigonometry all the time. You use what you have. Knowledge changes the way we think and work. With knowledge, you simply see the world differently.