5 squares are placed end to end as below (see pic). what is the perimeter of the rectangle formed by the squares?
2b) if the value of x is 2.1cm, what is the perimeter of the rectangle made in question 3.3) a square of side length 3in is placed on top of another square of side length 6in. what would be the total outer perimeter of the figure created by the two squares. ?

2b: If x is 2.1, then one side of the rectangle is 2.1, and another is 2.1*5=10.5.  Thus, the perimeter is 2*(2.1+10.5)=2*12.6=25.2.

3: One side of the square with side-length three will not be on the outside, so we have 3*3=9 inches perimeter from the square of side-length 3.  The square of side-length 6 has 3 from the top side missing from the outer perimeter, because it coincides with a side of the square of side-length three.  This square contributes 6*4-3=33 inches.  The total perimeter is 33+9=42 inches.