Let m = (313)4 and n = (322)4 . Find the base 4 expansion of m+n.
2017
Let m = (313)4 and n = (322)4 . Find the base 4 expansion of m+n.
- A.
(635)4
- B.
(32312)4
- C.
(21323)4
- D.
(1301)4
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Correct answer: D
Add the two numbers directly in base 4 using carries.
Units place: 3 + 2 = 5, which is 1 with a carry of 1 because 5 = 4 + 1.
Fours place: 1 + 2 + carry 1 = 4, which is 0 with a carry of 1.
Sixteens place: 3 + 3 + carry 1 = 7, which is 3 with a carry of 1.
Final carry becomes the 4^3 place: 1.
Therefore, m + n = (1301)₄.
Check (optional): Convert to decimal: (313)₄ = 3·16 + 1·4 + 3 = 55; (322)₄ = 3·16 + 2·4 + 2 = 58; sum = 113. Convert 113 to base 4: 113 ÷ 64 = 1 remainder 49; 49 ÷ 16 = 3 remainder 1; 1 ÷ 4 = 0 remainder 1; remainder 1 → (1301)₄.