What is the remainder when 7^55 is divided by 9?
Answer and explanation
Correct answer: C. 7
- Step 1: Find the repeating cycle of powers of 7 modulo 9. Step 2. Reducing the exponent 55 by the cycle length gives remainder 7. Answer: 7. Why not the others: 8 is what you get if you use a wrong cycle length. 0 is what you get if you use a wrong cycle length. 5 is what you get if you use a wrong cycle length.
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