first find the amount of red squares. there are 4 sections of red squares and 16 by 4 squares in each section. first find the number in each section by multiplying 16 squares long by 4 squares high 16*4=64 and that's for just one sections to find the total amount of red squares in all 4 sections we need to multiply 64 (the amount in one section) by the total amount of sections 4. resulting in 64*4=256 to find the blue squares used to fill the remainder of the quilt simply subtract the total red squares by the total squares like this 400-256=144, 144 is the amount of blue squares.