Answer the given questions about the indicated examples of this section.

In Example 3, if the machine part is the unshaded part (rather than the shaded part) of Fig. 2.80, what are the results?

Data from Example 3

A machine part is a square of side 3.25 in. with a quarter-circle removed (see Fig. 2.80). Find the perimeter and the area of the part. Setting up a formula for the perimeter, we add the two sides of length s to one-fourth of the circumference of a circle with radius s. For the area, we subtract the area of one-fourth of a circle from the area of the square. This gives

P = 2s + 2πs/4 = 2s +πs/2  A = s² – πs² /4

where s is the side of the square and the radius of the circle. Evaluating, we have

P = 2(3.25) + A = 3.252 TT (3.25) 2 TT (3.25) 4 = 11.6 in. = 2.27 in.