Question 35
MediumOriginal questionWhat is the last digit of ?
Show the answer and explanation
CorrectNot quiteAnswer D
Correct answer: D
Explanation
Last digits of powers of 3 repeat in a cycle of 4: 3, 9, 7, 1.
, so the last digit is the second in the cycle, 9.
Worth noting
7 is the third in the cycle: , not .
- Concept
- The last digit of a power
- Typical timeTypical
- 90 s
- Your timeYours
- —
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