Eventually you will have negative numbers when working with a decreasing pattern. There may be no negative absences. The only way is if those are leading into the people who are present. 4. 15 segments. n=n x (n-1)/ 2 5. Use the formula. 10 x (10-1) / 2 10 x 9 / 2 90/ 2 45 segments in a figure with 10 points.
