What is the greatest prime factor of 2^100 - 2^96?
A. 2
B. 3
C. 5
D. 7
E. 11
How is it 5? Can someone explain an easy way to solve this problem?
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Greatest prime factor?
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crackgmat007
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2^100 - 2^96
Pull out a factor of 2^96. This will leave you with:
2^96(2^4 - 1)
2^96(16 - 1)
2^96(15)
2^96(3*5)
The prime factors are 2, 3, and 5. 5 is the greatest.
Pull out a factor of 2^96. This will leave you with:
2^96(2^4 - 1)
2^96(16 - 1)
2^96(15)
2^96(3*5)
The prime factors are 2, 3, and 5. 5 is the greatest.
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crackgmat007
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