Question 1149332
w, whites
y, yellows
p, purples
k, variation constant


{{{w=ky^3/p}}}

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{{{k(y^3/p)=w}}}

{{{k=wp/y^3}}}

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{{{k=250*8/5^3}}}

{{{k=16}}}

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how many whites were there when there were 7 yellows and 4 purples?
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{{{w=16(y^3/p)}}}

Substitute for the given values.