¶ 2015 AMC 10A Problem 3
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:
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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