23 = 2 * A + 3
where A = 10.
Place value notation is a way of writing compactly multiplications and additions.
Children are taught place value notation in grade K. They are taught multiplication in grade 2. This is under the common core standards. Thus CCS are contradictory.
CCS claim to teach concepts. This is shown to be false in this case.
How did the math ed establishment miss this inconsistency?
- They are ignorant of the Peano Axioms and thus the math of elementary math.
- Working out Place Value Notation in a Peano Axioms context was not done until my book on Peano Axioms this year.
- They are running drill factories and have given up believing they can teach concepts to today’s mix of students.