powers simplification

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by DanaJ » Sat Aug 29, 2009 5:17 am
y can't be negative, since 1/(10^y) would be positive and you can't have negative = positive
y can't be greater than or equal to 1, since y would be much, much greater than 1/(10^y).
y can't be zero, since you'd have 0 = 1, which is incorrect.

This means that y is between 0 and 1, which is basically "no man's land". You can't get a fixed y just by guessing, or at least that's my take... You're gonna get a weird looking number! This is because powers of 10 in the (0, 1) area translate into roots of various degrees.

IMHO, the chances of seeing this on the real thing are extremely slim.

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by winnerhere » Sat Aug 29, 2009 5:53 am
Thanks dana.

I just needed the approach for this sum :)

Thanks for providing me the right approach

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Re: powers simplification

by Stuart@KaplanGMAT » Sat Aug 29, 2009 9:41 am
winnerhere wrote:y=1/(10^y)

Find Y
Is this an actual GMAT question?

If so, please provide answer choices. By far, backsolving would be the easiest way to solve.

As Dana noted, the answer is going to be very weird, which is why I wonder if it's a real GMAT question. The only way I can imagine that it would be is if the answer choices were ranges, eg:

a) greater than 10
b) 10
c) between 1 and 10
d) between 0 and 1
e) less than 0
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