Answer:
360 tiles.
Explanation:
Mariah builds a table top using square tiles.
There are 12 rows of tiles and 30 tiles in each row.
You have to add 30 tiles 12 times to find the number of total tiles.
or you just multiply 30 by 12 to get the number.
The total number of tiles Mariah used = 30 × 12 = 360 tiles.
Mariah used 360 tiles to build a tabletop.