9 + 9 + 9 = 27; with an array of 3 rows and 3 columns
9 + 9 + 9 = 27; with an array of 3 rows and 9 columns
9 + 9 + 9 = 36; with an array of 3 rows and 9 columns
9 × 1 to 9 × 10, the sum of the two digits in the product is always 9.
4 × 8 × 2