What is the units digit of (1234)²?
A6
B9
C4
D16
Answer & Solution
Correct answer: A. 6
The units digit of n² depends only on the units digit of n. The units digit of 1234 is 4, and 4² = 16, whose units digit is 6. So (1234)² ends in 6. (Option D '16' confuses units digit with the full square of 4 — only the units digit '6' is requested.)
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