SOLUTION: Two quantities, p and q^3, are in inverse proportion. It is known that p=540 for a particular value of q. Find the value of p when the value of q is increased by 100%

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Question 1033956: Two quantities, p and q^3, are in inverse proportion. It is known that p=540 for a particular value of q.
Find the value of p when the value of q is increased by 100%
Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!
If two quantities p and q^3 are in inverse proportion then p%2Aq%5E3+=+k for some proportionality constant k.
It is given that 540%2Aq%5E3+=+k for some q.
Increasing q by 100% means doubling it.
==> p%2A%282q%29%5E3+=+k <==> 8pq%5E3+=+k.
Since 540%2Aq%5E3+=+k for some q, ==> 8p%2Aq%5E3+=+540%2Aq%5E3 ==> p = 67.5.