If 8^x = 2^12, what is x?
A. 2
B. 3
C. 4
D. 5
E. 6
The OA is the option C.
What is the fastest way to solving this PS question? I would appreciate any help.
If 8^x = 2^12, what is x?
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We need to rewrite the powers with the SAME BASES.M7MBA wrote:If 8^x = 2^12, what is x?
A. 2
B. 3
C. 4
D. 5
E. 6
In this case, we can rewrite them with a common base of 2
Given: If 8^x = 2^12, what is x?
Rewrite 8 as 2³ to get: (2³)^x = 2^12
Apply Power of a Power rule to get: 2^(2x) = 2^12
So, we can conclude that: 2x =12
Solve: x = 6
Answer: 6
Cheers,
Brent
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If we have equal bases, then we can equate the exponents. Since 8 = 2^3, we see that 8^x = (2^3)^x = 2^3x. Thus, we have:M7MBA wrote:If 8^x = 2^12, what is x?
A. 2
B. 3
C. 4
D. 5
E. 6
2^(3x) = 2^12
3x = 12
x = 4
Answer: C
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Hi All,
We're told that 8^X = 2^12. We're asked for the value of X. This question can be solved in a number of different ways - depending on how you choose to do the math. Sometimes how you choose to "see" a GMAT question can give you a significant 'shortcut' in solving that question.
We know that 2^12 is just a bunch of 2s multiplied together (twelve 2s in fact). If we take three of those 2s and multiply them, we get (2)(2)(2) = 8. Since there are twelve 2s, we can rewrite THAT large calculation four 'trios' of 8....(8)(8)(8)(8). This is 8^4, so X=4.
Final Answer: C
GMAT assassins aren't born, they're made,
Rich
We're told that 8^X = 2^12. We're asked for the value of X. This question can be solved in a number of different ways - depending on how you choose to do the math. Sometimes how you choose to "see" a GMAT question can give you a significant 'shortcut' in solving that question.
We know that 2^12 is just a bunch of 2s multiplied together (twelve 2s in fact). If we take three of those 2s and multiply them, we get (2)(2)(2) = 8. Since there are twelve 2s, we can rewrite THAT large calculation four 'trios' of 8....(8)(8)(8)(8). This is 8^4, so X=4.
Final Answer: C
GMAT assassins aren't born, they're made,
Rich