As per the basic time work rule ....
1/A+1/B = 5/6
1/B+1/C = 2/3
1/C +1/A = 1/2
Adding the above 3 equations we get
1/A+1/B+1/C = 1
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AleksandrM
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Can you please show how you added the three above. I got to the first part without a problem with 5/6, 2/3, and 1/2, but could not move beyond that. I tried substitution, combining, but I ended up with A or B or C equaling a negative number.
Adding all three of those would give us:AleksandrM wrote:Can you please show how you added the three above. I got to the first part without a problem with 5/6, 2/3, and 1/2, but could not move beyond that. I tried substitution, combining, but I ended up with A or B or C equaling a negative number.
2( 1/A + 1/B + 1/C).
And then divide both sides by 2, to get 1/A + 1/B +1/C
Hope this helps!
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AleksandrM
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No, that does not help at all. In fact, it confused me more. Why are you multiplying the three fractions by 2. And as far as the "other side" goes, what is on the other side.
If it is: 1/A + 1/B + 1/C = 1/x
Then I do not see where the 2 came from, etc, etc, etc.
If it is: 1/A + 1/B + 1/C = 1/x
Then I do not see where the 2 came from, etc, etc, etc.
Ok, Trial 2:AleksandrM wrote:No, that does not help at all. In fact, it confused me more. Why are you multiplying the three fractions by 2. And as far as the "other side" goes, what is on the other side.
If it is: 1/A + 1/B + 1/C = 1/x
Then I do not see where the 2 came from, etc, etc, etc.
These are the three equations:
......................................................................1/A+1/B = 5/6
......................................................................1/B+1/C = 2/3
......................................................................1/C +1/A = 1/2
________________________________________________________________
Add all three (+) {1/A + 1/B} + {1/B + 1/C} + {1/C + 1/A} = {5/6} +{2/3} +{1/2}
Combining like terms (which in this case are the 1/A, 1/B and 1/C)
2 (1/A) + 2(1/B) + 2(1/C) = 5/6 + 2/3 + 1/2
Or, 2 { 1/A +1/B + 1/C } = 12 /6
Or, 2{ 1/A +1/B + 1/C } = 2
Or, { 1/A +1/B + 1/C } = 2/2
Or, 1/A + 1/B +1/C = 1 day
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AleksandrM
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No probs Aleksandr.AleksandrM wrote:Alright!!!Thanks so much musiq.
Thats what this forum is for. I help you, you help me.
Together we crack the GMAT
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