My goals for this site are to have it:
– Offer helpful approaches to topics that are frequent stumbling blocks for students.
– Encourage both students and teachers to approach math conceptually as well as procedurally.
– Let folks who find math challenging at times know that they are not alone, that many people who appear to be “good at math” still experience the same challenges
– Encourage people to be patient with themselves as they seek to master new concepts and skills. Patience and perseverance are two critical attributes when seeking to master any concept or skill.
– Encourage people to ask questions (of me or others) and engage in dialog with others (either written or verbal) about quantitative topics. I often learn a great deal more about a topic by writing or talking about it than I do by just reading about it.
My background includes:
– Tutoring math students for 30 years
– Teaching high school students both full-time and as a substitute
– Teaching adults at community services, trade show, and organizational workshops
MathMaine 
I came upon an unusual math symbol. |U{n}| there is an ‘n=0’ under the U and a 10 at the top of the U. Can you tell me what it means?
I would think it would refer to a Union of 11 sets, though I would normally expect to see something like an “a sub n” after the union symbol if it were the union of a bunch of sets. Given just the “n” after the Union symbol in set-notation curly braces, I would be inclined to think it refers to the set of numbers from 0 through 10: {0, 1, 2, 3 , 4, 5, 6, 7, 8, 9, 10}
Thank you for the reply. Allow me to add to my description. I came across this symbol on a clock face and the symbol is used to represent the 11 o’clock position. Does that make sense? Is it representing 11 by the number of sets?
Yes, that makes sense, as there would indeed by 11 numbers in that set. If they had wanted to be a bit more clear about it, they could have used n=1 to 11. If they wanted to be even more obscure, they could have used something like n=42 to 52…