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I have a rectangle with a known area and a known ratio of length/width. How do I calculate the length and width.

Area: 1500 sq ft Ratio: 241 / 625 = .386

How do I calculate the length and width in feet.

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    Have you looked at this question? I think it should help. – 2017-02-07
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    Solve for $k$ in $241k\times 625k = 1500$, then plug and chug – 2017-02-07

2 Answers 2

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Let the length of the rectangle be $l $ and the width be $w$. We know the area of the rectangle is $A = lw \tag {1}$.

Now it is given that $\frac {l}{w} = \frac {241}{625} \Rightarrow l = \frac {241}{625}w \tag {2}$.

Now substituting $(2)$ in $(1)$, we have, $$A = \frac {241}{625}w^2 =1500$$ $$w = \sqrt {\frac {1500\times 625}{241}} = \frac {10\times 25\times \sqrt {15}}{\sqrt {241}} = \frac {250\sqrt {15}}{\sqrt {241}} $$

Now I leave it to you to find $l$ using $(2)$. Hope it helps.

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    The sq rt of 1500*625/241 = length – 2017-02-07
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    This answer was most helpful to me in understanding the concept. – 2017-02-07
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Hint:

Area$=$ length $\times$ width,

and

length$=\frac{241}{625}$ width,

so:

Area$= \frac{241}{625}$ width $\times$ width $= \frac{241}{625} x^2=1500$

Can you solve for $x$?

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    If, as write in OP, the ratio length/width is $241/625$, the width is greater than the length. – 2017-02-07