Answer:
18
Step-by-step explanation:
First design: upholstery and wood
Second design: upholstery
For the first design the possible chairs we can make are 6 with the first type of wood and 6 with the second one. Therefore we sum both results=12.
For the second the possible chairs we can make are 6.
The total of possibles chairs we can make are 6 + 12 = 18.