Answer:
Length x height x width.
Explanation:
Examples:
1 x 2 x 3 = 1 x 2 = 2 + 0 = 2 x 3 = 3 + 3 = 6 so the answer is 6.
2 x 3 x 2 = 2 x 3 = 3 + 3 = 6 x 2 = 6 + 6 = 12 so the answer is 12.
Here's one more in a different way:
3 x 5 x 4 = 5 + 5 + 5 = 15 = 15 + 15 = 30 x 2 = 30 + 30 = 60.