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gmattokyo
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If mn != 0, is 1/m-1/n=6 ? 1. n - m = 6mn 2. n = 4m 28 Oct 2009, 09:20
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87% (00:39) correct 13% (00:50) wrong based on 52 sessions

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If mn != 0, is \(1/m-1/n=6\) ?

1. n - m = 6mn
2. n = 4m



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If mn != 0, is 1/m-1/n=6 ? 1. n - m = 6mn 2. n = 4m 28 Oct 2009, 09:27
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isn't the answer A

n-m=6mn ==> divide both sides by mn and we get 1/m-1/n=6
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If mn != 0, is 1/m-1/n=6 ? 1. n - m = 6mn 2. n = 4m 28 Oct 2009, 11:18
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You are correct, A.

What I did during solving for B was substitute n=4m to get m=1/8, but didn't realize that for other values of m, the statement is not true.
darn-it these mistakes are proving to be expensive :(
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If mn != 0, is 1/m-1/n=6 ? 1. n - m = 6mn 2. n = 4m 28 Oct 2009, 11:52
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gmattokyo
If mn != 0, is \(1/m-1/n=6\) ?

1. n - m = 6mn
2. n = 4m
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I don't get this.

You states that mn! = 0. Rephrase to get m*(m-1)(m-2)(...)*n*(n-1)(n-2)(...) = 0. That implies that either m or n is zero in which case \(1/m-1/n=6\) is not defined.

Could anybody clarify?
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If mn != 0, is 1/m-1/n=6 ? 1. n - m = 6mn 2. n = 4m 28 Oct 2009, 12:10
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andershv
gmattokyo
If mn != 0, is \(1/m-1/n=6\) ?

1. n - m = 6mn
2. n = 4m

I don't get this.

You states that mn! = 0. Rephrase to get m*(m-1)(m-2)(...)*n*(n-1)(n-2)(...) = 0. That implies that either m or n is zero in which case \(1/m-1/n=6\) is not defined.

Could anybody clarify?
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How you rephrased mn! = 0. to get m*(m-1)(m-2)(...)*n*(n-1)(n-2)(...) = 0 ?

sorry, I dont get this
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If mn != 0, is 1/m-1/n=6 ? 1. n - m = 6mn 2. n = 4m 28 Oct 2009, 12:43
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srini123
andershv
gmattokyo
If mn != 0, is \(1/m-1/n=6\) ?

1. n - m = 6mn
2. n = 4m

I don't get this.

You states that mn! = 0. Rephrase to get m*(m-1)(m-2)(...)*n*(n-1)(n-2)(...) = 0. That implies that either m or n is zero in which case \(1/m-1/n=6\) is not defined.

Could anybody clarify?

How you rephrased mn! = 0. to get m*(m-1)(m-2)(...)*n*(n-1)(n-2)(...) = 0 ?
sorry, I dont get this
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Example 5! = 5*4*3*2*1 = 5*(5-1)(5-2)(5-3)(5-4)
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If mn != 0, is 1/m-1/n=6 ? 1. n - m = 6mn 2. n = 4m 28 Oct 2009, 13:27
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Even on first glance it looks like n! but taking a second look states that "mn is not equal to zero"

I will go with option A
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If mn != 0, is 1/m-1/n=6 ? 1. n - m = 6mn 2. n = 4m 28 Oct 2009, 13:35
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:lol:

Ok. Wasn't aware of this notation.

Thanks for the heads up!
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If mn != 0, is 1/m-1/n=6 ? 1. n - m = 6mn 2. n = 4m 28 Oct 2009, 15:24
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OMG, u thought of a factorial for "not equal" to sign ? well one can read it that way too...

is this called lateral thinking ? lol
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gmattokyo
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If mn != 0, is 1/m-1/n=6 ? 1. n - m = 6mn 2. n = 4m 28 Oct 2009, 19:37
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sorry if the notation confused you. the Q meant mn 0



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This topic has been closed and archived due to inactivity or violation of community quality standards. No more replies are possible here.
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