Answer: There are 42 products he can have at maximum.
Step-by-step explanation:
Since we have given that
Number of products displays = 12
Number of shelves six products have = 4
Number of shelves six products have = 3
So, total number of shelves first six products have
Total number of shelves next six products have
So, the maximum number of products that he can have is given by
Hence, there are 42 products he can have at maximum.