Answer:
4 are playing at the sand table
Step-by-step explanation:
There were 9 kids at Kenneth's preschool and 3 were playing, thats one third of the kids(3x3=9). One third of 12 is 4(3x4=12) Basically since there were 9 total kids, and 3 at the sand table, they are divided equally in groups of three so you just divide 12 by 3 too and thats how you get 4