2^(-2k) < 16. What is the value of k?
1) k-12 is odd
2) k-12 is prime
161) What is the value of K
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2^-2k < 16
or k<64
From 1 ..nothing can be concluded
From 2
again..k-12 can be anything like 2,3,5,7..47..not sufficient
combining..
k-12 can be 3,5,7..47....not sufficient
Ans option E
What is the OA?
or k<64
From 1 ..nothing can be concluded
From 2
again..k-12 can be anything like 2,3,5,7..47..not sufficient
combining..
k-12 can be 3,5,7..47....not sufficient
Ans option E
What is the OA?
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Upon solving the inequality we get, -2k > 4 for the inequality 2^(-2k) < 2^4 to hold.
Hence k > -2,
1 says, k-12 is odd, k can be 23 or -9. In former 2^(-2k) is >16 and in the latter it is not. Hence, 1 not sufficient.
2 says, k-12 is prime. The smallest prime is 2 hence, k>=14, hence 2 alone is sufficient.
Hence answer is B.
Hence k > -2,
1 says, k-12 is odd, k can be 23 or -9. In former 2^(-2k) is >16 and in the latter it is not. Hence, 1 not sufficient.
2 says, k-12 is prime. The smallest prime is 2 hence, k>=14, hence 2 alone is sufficient.
Hence answer is B.