To find an expression equivalent to the sum \( 18 + 12 \), we can break down the components shown in the model.
You have:
- 3 rows of 6 orange squares: \( 3 \times 6 = 18 \)
- 3 rows of 4 blue squares: \( 3 \times 4 = 12 \)
From this, we can express the total as: \[ 18 + 12 = (3 \times 6) + (3 \times 4) \]
This means one expression that is equivalent to \( 18 + 12 \) is: \[ (3 \times 6) + (3 \times 4) \]
You can also express this as: \[ 3 \times (6 + 4) \]
Thus, another equivalent expression could be: \[ 3 \times 10 \]
So, both \( (3 \times 6) + (3 \times 4) \) and \( 3 \times (6 + 4) \) are correct answers, and specifically, the answer to fill in would be: \[ 3 \times (6 + 4) \]