Problem:
Ann made a -step staircase using toothpicks as shown in the figure. How many toothpicks does she need to add to complete a -step staircase?
Answer Choices:
A.
B.
C.
D.
E.
Solution:
Five vertical and five horizontal toothpicks must be added to complete the fourth step. Six vertical and six horizontal toothpicks must be added to complete the fifth step. This is a total of toothpicks added.
The problems on this page are the property of the MAA's American Mathematics Competitions