First:

Sally has five red cards numbered 1 through 5 and four blue cards numbered 3 through 6. She stacks the cards so that the colors alternate and so that the number on each red card divides evenly into the number on each neighboring blue card. What is the sum of the nummbers on the middle 3 cards?


Two:

A semicircle of diameter 1 sits at the top of a semicircle of diameter 2. The shaded area inside the smaller semicircle and outisde the larger semicircle is called a lune. Determine the area of this lune.