2026 AMC 8

What is the value of the following expression?

$1 + 2 - 3 + 4 + 5 - 6 + 7 + 8 - 9 + 10 + 11 - 12$

In the array shown below, three $3$s are surrounded by $2$s, which are in turn surrounded by a border of $1$s. What is the sum of the numbers in the array?

$\begin{array}{ccccccc} 1 & 1 & 1 & 1 & 1 & 1 & 1 \\ 1 & 2 & 2 & 2 & 2 & 2 & 1 \\ 1 & 2 & 3 & 3 & 3 & 2 & 1 \\ 1 & 2 & 2 & 2 & 2 & 2 & 1 \\ 1 & 1 & 1 & 1 & 1 & 1 & 1 \end{array}$

Haruki has a piece of wire that is $24$ centimeters long. He wants to bend it to form each of the following shapes, one at a time.

• A regular hexagon with side length $5$ cm.
• A square of area $36$ cm².
• A right triangle whose legs are $6$ and $8$ cm long.

Which of the shapes can Haruki make?

Brynn's savings decreased by $20\%$ in July, then increased by $50\%$ in August. Brynn's savings are now what percent of the original amount?