文档介绍：Math 302A
Section 4
January 16, 2007
Pieces of Counting Grids
Below are two pleted Alphabitian counting grids. In each grid, try to determine the value of the number in each square occupied by a question mark, using reasoning – that is , without simply filling in all the blank boxes. Then justify your answer.
AA
AB
AC
AD
B0
?
?
?
BBB
?
?
In this grid, we are dealing with multidigit numbers. Just as we find that young children can count confidently and quickly with two digit numbers and then be more tentative with three-digit numbers, so this table will require you to think more carefully about what the numbers mean, which will in turn cause you to consider the fundamental ideas of what it means to be a base and what place value means.
Explain “why” es after ADD, as if you were talking to a student who got the answer wrong and is struggling to understand the new system. If you find that you can explain “how” but not “why”, it might help to build DD with manipulatives and add a little cube.
Operations in the Alphabetia system:
To get the most out of this activity, do these problems as if you were a member of the tribe. This means that you have never heard of 1, 2, 3, 4, etc and it also means that you do not have any knowledge of formal procedures for adding, subtracting, multiplying, or dividing. Model the problems using manipulatives.
Raga has AC Sheep and