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Bebras 2019 - Level 2 Question 12

BEBRAS · Bebras 2019 - Level 2

Question 12

Three beaver chemists have very large quantities of four substances (triangle, right triangle, filled square and square frame) and are trying to create a new four-point substance. The original substance symbols are shown below.

Question illustration

Question illustration

Each chemist will work for two days. However, only one chemist works each day, and only one chemical reaction can be performed in a day. A chemical reaction transforms several substances into a new substance. Each chemist knows the following reactions:

Question illustration

Editable transcription (the descriptive names refer to the original shapes):

| Chemist | First reaction | Second reaction |
|---|---|---|
| Carly | Triangle + right triangle → circle missing a quadrant | Circle missing a quadrant + arrow → circle |
| Paula | Square frame + right triangle → pentagon | Square frame + filled square → arrow |
| Barry | Filled square + pentagon → diamond | Triangle + circle + diamond → four-point product |

Which of the following work orders does not allow the chemists to complete their task?
  1. Carly – Paula – Barry – Paula – Carly – Barry.
  2. Carly – Paula – Barry – Carly – Paula – Barry.
  3. Paula – Paula – Carly – Carly – Barry – Barry.
  4. Paula – Barry – Paula – Carly – Carly – Barry.