2050.44 – Parentheses Insert

Insert parentheses and arithmetic symbols (e.g +, -, x) any way you want to make the statement true.

2  1  2  3  2  2  1 = 122 \ \ 1 \ \ 2 \ \ 3 \ \ 2 \ \ 2 \ \ 1 \ = \ 12
Solution

Here's one way:

2×(1+2×3)−2×(2−1)=12.2 \times (1 + 2 \times 3) - 2 \times (2 - 1) = 12.

Any others?

If your students are just getting used to parentheses and if they liked figuring this problem out, you could make some more for them--even put one on a quiz as an extra-credit problem. Better, have the kids make some up to try on each other.