Base Systems (Hard)
Late AMC 10/12 through early AIME — dense computation.
Base Systems: core idea
Arithmetic in base.
Example problem: hint and answer
Evaluate in base ten.
Hint: Expand place values or carry and borrow in the stated base. Answer: 73.
Practice (9 problems — type your answers)
1. Write in base .
2. If , find .
3. Compute in base .
4. Find the least base such that is divisible by .
5. Evaluate in base ten.
6. Find if .
7. Compute in base .
8. Decimal is . Find .
9. Find .