1989 AJHSME Problems/Problem 1
Contents
[hide]Problem
Solution
We make use of the associative and commutative properties of addition to rearrange the sum as
Solution 2
Or, we can just combine the first, second, third, fourth, and last terms in each parentheses. This gives us:
\begin{align*} (1+9)+(11+19)+(21+29)+(31+39)+(41+49), (Error compiling LaTeX. Unknown error_msg)
which gives us $$ (Error compiling LaTeX. Unknown error_msg)\begin{align*} 10+30+50+70+90 &= \boxed{250}.$
~DuoDuoling0
See Also
1989 AJHSME (Problems • Answer Key • Resources) | ||
Preceded by First Problem |
Followed by Problem 2 | |
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