¶ 1992 AMC8 Problem 6
Problem:
Suppose that
means . For example,
is . Then the sum
Answer Choices:
A.
B.
C.
D.
E.
Solution:
Note that
where and ; i.e., the sum of two 'triangular expressions' is the value of the 'triangular expression' obtained by summing the respective components. It follows that the required sum is .
Answer: .
The problems on this page are the property of the MAA's American Mathematics Competitions