CRACK THE CODE · GRADE 4
Paleontologist Dig Site Decoder
Use your paleontologist math skills to find the missing fossil weights and reveal the secret four-digit combination to the specimen transport case.
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 15. 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
- 3.10−=
- 4.×−=CODE 2
- 5.×−=
- 6.×+=CODE 3
- 7.10−=
- 8.3+2=CODE 4
- 9.3+2=
- 10.100+=
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 reinforced titanium fossil.
Show answer key (for grown-ups)
Key: square = 13 · hexagon = 9 (hidden) · moon = 7 (hidden) · cross = 11 (hidden) · triangle = 14 · heart = 8
Every symbol is a whole number from 1 to 15.
Vault code: 7641