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willbeatthegmat
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exponents prob 2....
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Source: Beat The GMAT — Problem Solving |
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sureshbala
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Could you please check the question (or the source) once again. Because in GMAT DS normally you will not have two contradictory statements.
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willbeatthegmat
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marcusking
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a.) Given that the sqrt(625) is 25
that gives us that 5^x = 25 and thus x = 2
A is sufficient
b.) Given that 625 is 25^2 then 625 * 25 = 15625 and we know that
that gives us 5^x = 25 and thus x = 2
B is sufficient
So Each statement alone is sufficient
that gives us that 5^x = 25 and thus x = 2
A is sufficient
b.) Given that 625 is 25^2 then 625 * 25 = 15625 and we know that
that gives us 5^x = 25 and thus x = 2
B is sufficient
So Each statement alone is sufficient
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willbeatthegmat
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cjb
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But (-25)^2 also equals 625.marcusking wrote:a.) Given that the sqrt(625) is 25
that gives us that 5^x = 25 and thus x = 2
A is sufficient
Not sure what that would mean in this case, as I don't know how to solve
5^x = -25
Nonetheless, I would answer B, not D.
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marcusking
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hmmmm........willbeatthegmat wrote:that looks very simple n obvious...wat if y = -25....wat wud b d value of x in stat 1
I don't think this is possible. Since the base of the number is 5 and not -5 I don't think there is any power you can raise it to that would cause it to be -25. If we try raise it to any negative root we end up getting a decimal. If we try and raise it to any fraction or decimal of a power we still get a positive number.
Anyone else
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