a) 30 squares b) The areas are: $16\ in^2$, $9\ in^2$, $4\ in^2$ and $1\ in^2$. c) Area Addition Postulate
Work Step by Step
a) Count to find that there are 30 squares. b) There are 4 red squares. Count the small squares, which are each 1 in, to find the dimensions of each square and compute the area. $A_1=s^2=4^2=16$ $A_2=s^2=3^2=9$ $A_3=s^2=2^2=4$ $A_4=s^2=1^2=1$ c) Sum the results in part b. $A=A_1+A_2+A_3+A_4=16+9+4+1=30$ The equality of the two results supports the Area Addition Postulate.