Let $n$ be a positive integer with $n \leq 20$. The sum $$1 + 2 + 3 + \cdots + n$$ is divisible by 9. Accordingly, what is the sum of the possible values of n? A) 50 B) 52 C) 56 D) 60 E) 64
Let $n$ be a positive integer with $n \leq 20$. The sum
$$1 + 2 + 3 + \cdots + n$$
is divisible by 9. Accordingly, what is the sum of the possible values of n?\\
A) 50\\
B) 52\\
C) 56\\
D) 60\\
E) 64