Hey guys, can you help me with this question, see enclosed screenshot of the question. Why is the answer 2/3?

I thought to formulate as

1 fence = (1/x + 1/2x) . k

1/k = 1/x + 1/2x

1/k = 1/x + 2x

x+2x = k

3x = k

hence k = 1/3

Hey guys, can you help me with this question, see enclosed screenshot of the question. Why is the answer 2/3?

I thought to formulate as

1 fence = (1/x + 1/2x) . k

1/k = 1/x + 1/2x

1/k = 1/x + 2x

x+2x = k

3x = k

hence k = 1/3

I don’t understand this step: your first one looks fine, but I don’t know how you inferred that \frac{x}{2} is 2x. Your subsequent step is similarly confusing.

Apologies

1 fence = (1/x + 1/2x) . k

*divide both sides by k*

1/k = 1/x + 1/2x

*1 over x + 1 over 2x can be changed to 1 over x + 2x*

1/k = 1 / (x + 2x)

*cross multiply*

x+2x = k

3x = k

hence k = 1/3

but maybe the confusing step is what i did wrong?

first isolate this :

\dfrac{1}{x}+\dfrac{1}{2x}

try to make denominator same

As Leaderboard quoted earlier your equation is correct but you’re making mistake while making denominator the same

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You mean

\frac{1}{x} + \frac{1}{2x} = \frac{1}{x + 2x}

(hint: if that was a QC question with Quantity A the LHS and Quantity B the RHS, the answer would be D. In other words, that’s an illegal operation)

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got it, thank u

got it thankkssssssssss <3