Answer: 16
Step-by-step explanation: If 3 black circles equal 30, we can divide that by 3 and get 10. If 1 black circle and 2 white circles equal 18, we can subtract 10 and get left with 2 white circles worth 8, which means a white circle is 4. A white circle minus a square is 2, which means a square is 2. So we put this all together and get 16.
