CRACK THE CODE · GRADE 4
The Redstone Captain's Obsidian Chest
Decode the values of the pirate-themed blocks and items to find the four-digit combination for the captain's vault.
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.(−)×=
- 4.10−=CODE 2
- 5.×=
- 6.×−=CODE 3
- 7.(+)×=
- 8.×−=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 obsidian chest locked.
Show answer key (for grown-ups)
Key: pentagon = 9 · moon = 7 (hidden) · hexagon = 11 (hidden) · ring = 10 (hidden) · lightning bolt = 8 · diamond = 13
Every symbol is a whole number from 1 to 15.
Vault code: 7722