Answer: 36 hotdogs
Step-by-step explanation: You need to find the least common multiple of 9 and 12.
You can check by multiplying 9 and 12 by consecutive whole numbers until you find a number that they match.
Example:
9*1= 9 , 9*2=18, 9*3= 27, 9*4=36, 9*5=45
12*1=12, 12*2=24, 12*3 =36
They both share 36.