SOLUTION: The length of rectangular box with a fixed height varies directly as the volume and inversely as the width. If the length is 15 cm when the volume is {{{l260cm^3}}} and the

Algebra ->  Expressions-with-variables -> SOLUTION: The length of rectangular box with a fixed height varies directly as the volume and inversely as the width. If the length is 15 cm when the volume is {{{l260cm^3}}} and the       Log On


   

Question 1087621: The length of rectangular box with a fixed height varies directly as the volume and
inversely as the width. If the length is 15 cm when the volume is l260cm%5E3 and the width is 8 cm, find the length when the volume is 840+cm%5E3 and the width is 5 cm.
Answer by josgarithmetic(39838) About Me  (Show Source):
You can put this solution on YOUR website!
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The length of rectangular box with a fixed height varies directly as the volume and
inversely as the width. If the length is 15 cm when the volume is l260cm^3 and the width is 8 cm,
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L, length
k, variation constant
w, width
v, volume

L=kv%2Fw
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Lw%2Fv=k
k=15%2A8%2F1260
k=120%2F1260
k=2%2A2%2A3%2F%282%2A7%2A3%2A3%29
k=2%2F21
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highlight%28L=%282%2F21%29v%2Fw%29

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find the length when the volume is 840+cm%5E3 and the width is 5 cm.
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Just substitute the values and evaluate L.