CRACK THE CODE · GRADE 3
Cretaceous Code Breaker
Find the hidden number values for the triceratops skull, T-rex tooth, and raptor claw to crack the four-digit combination lock on the heavy field chest.
Each shape stands for a number. Work out the missing ones first, then solve the shape equations and read off the 4-digit code. Do it here or print the sheet — the answer key comes with it.
The key
Every symbol is a whole number from 1 to 12. A number in front of a shape means multiply: 2 stars = 2 x star.
Find the missing values
Some shapes in the key are missing. Use these equations to work them out, then write them into the key. Take them in order.
Crack these
- 1.×=
- 2.++=CODE 1
- 3.2+=
- 4.×−=CODE 2
- 5.×=
- 6.++=CODE 3
- 7.2+=
- 8.×−=CODE 4
- 9.3−=
- 10.10+=
The vault code
Take the ones digit of your answers to problems 2, 4, 6, 8 (the ones tagged CODE 1–4), in that order. That opens the paleontologists locked steel.
Show answer key (for grown-ups)
Key: diamond = 11 · moon = 3 · pentagon = 4 · cross = 12 (hidden) · triangle = 9 · star = 6 (hidden)
Every symbol is a whole number from 1 to 12.
Vault code: 9274