Quantitative Aptitude • Number System & SimplificationMedium
What is the unit digit of 9^61?
A. 4
B. 9✓ Correct Answer
C. 1
D. 2
💡 Solution & Explanation
The unit digits of powers of 9 repeat in a cycle of 2: 9, 1. Divide the power by 2: 61 ÷ 2 leaves a remainder of 1, which means position 1 in the cycle. So the unit digit of 9^61 is 9. Only the last digit of the base matters for this pattern.
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