Which of the following is a step in bisecting a line segment? A. Adjust the compass so that it is less than one half of the segment length.

B. Use a compass to draw concentric circles from an endpoint.

C. Use a compass to swing an arc on either side of the segment for each endpoint.

D. Use a ruler to measure the given segment, in inches.

Start with "a ratio of 7 to 4:"  

  7                                    number of pepperoni pizzas        585
---   Equate this ratio to =
 4                                      number of plain pizzas                  p

Solve this equation of ratios for p, the number of plain pizzas sold.

Cross multiply:  7p = 4(585).  Divide both sides by 7 to get the approx number of plain pizzas that are sold.  Your final answer, the total number of pizzas sold, will then be 585 plus the value of p that you've just found.