Biased most likely means not random in this context. The actual definition is "unfairly prejudiced for or against someone or something"
Each rug is 1/8 of the floor space. So, 4 rugs would cover half of the floor space. Multiply, then reduce.
4(1/8)=4/8 or 1/2
16, 24, 32
and it goes on, and on.
To make a square blanket, you need to calculate the squareroot of 120, which is 10,954... so the biggest number is 10x10 peaces of fabric you can use to create a square blanket. These are 100 (so 20 are left over). To create a bigger square blanket of 11×11 peaces (11^2 = 121) you need one more peace of fabric. One peace is six inches, the blanket is 10 peaces long (6×10=60) The size would be 60inchesx60inches= 3.600 inches.