Answer:
Customers:
Copy Copy and bind
12 20
Processes:
Process - Binding - Copy - Checkout.
Photocopy customer visit copy and checkout. While copy & bind process customer visit all 3 processes
The table below is illustrating the demand:
Process Binding Copy Checkout
Copy & bind customers 20 20 20
Only photocopy customers 12 12
Total customer for each process 20 32 32
So, the total demand of the 3 processes is equals to 84 [20+32+32]