Answer: There are 16 wireless and 64 regular keyboards.
Step-by-step explanation:
Since we have given that
Cost of regular keyboards = $75
Cost of wireless keyboards = $106
Let the number of wireless keyboards be 'x'.
Let the number of regular keyboards be '4x'.
Total cost = $6,496
According to question, we get that
[tex]75\times 4x+106\times x=6496\\\\300x+106x=6496\\\\406x=6496\\\\x=16[/tex]
So, there are x = 16 wireless keyboards and 16×4 = 64 regular keyboards.
Hence, there are 16 wireless and 64 regular keyboards.