Find a common factor of (4^743 + 4^343) and (4^747 + 4^347).
Aptitude
Numbers
Difficulty: Medium
Choose an option
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A4^343(4^400 + 1)
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B4^343(4^400 − 1)
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C4^344(4^400 + 1)
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D4^400 − 1
Answer
Correct Answer: 4^343(4^400 + 1)
Explanation
Given data
- S1 = 4^743 + 4^343
- S2 = 4^747 + 4^347
Concept / Approach
- Factor out common powers of 4 and compare.
Step-by-step factorization
S1 = 4^343(4^400 + 1)S2 = 4^347(4^400 + 1) = 4^343 · 4^4 · (4^400 + 1)Thus, 4^343(4^400 + 1) divides both S1 and S2.
Why alternatives fail
- 4^343(4^400 − 1): the (4^400 − 1) factor is not present in either expression.
- 4^344(4^400 + 1): divides S2 but not S1 (S1 has only 4^343).
- 4^400 − 1: unrelated to the given sums.
Final Answer
Common factor = 4^343(4^400 + 1).