Detailed description

Two rows of numbers. The top row is multiples of 3 (3, 6, 9, 12, 15, 18, 21, 24, 27…) with the 3 in bold and 12 highlighted by a star.
The bottom row is multiples of 4 (4, 8, 12, 16, 20, 24, 28, 32 …) with the 4 in bold and 12 highlighted by a star.