CPM Homework Help : CCA2 Problem 6-10

Each cube below is 1 cm on a side.

Figure I: 1 cube. Figure II: 1 layer of 5 cubes, in an x shape, arranged with, 3 across in a row, 3 in center column, sharing the center cube. Figure III: question mark. Figure IV: 1 layer of 13 cubes, in an x shape, arranged with, 7 across in a row, 7 in center column, sharing the center cube.

Based on the pattern, find the volume of Figure III.
Hint (a):
What is the difference between Figure (II) and Figure (IV)?
Make a table.
If the pattern continues, write an expression to represent the volume of figure N. What kind of sequence is this?
Hint (b):
Find the common difference between the volumes of each figure.
Answer (b):
$4n−3$ , arithmetic