equation solving

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equation solving

by winnerhere » Sun May 17, 2009 8:42 am
Find the value of



(0.0758 * 0.0758 * 0.0758 + 0.9242 * 0.9242 * 0.9242 )/(0.0758 * 0.9242 + 0.0758 * 0.9242 + 0.0758 * 0.9242 )

(a) 0.8484 (b) 1.0758 (c) 2 (d) 1

It is (a^3 + b^3)/3ab

But how could i simplify this equation to get the answer easily.
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by dumb.doofus » Sun May 17, 2009 9:24 am
Notice first that 0.0758 + 0.9242 = 1

Now the equation looks like (a^3 + b^3)/3ab

(a + b)^3 = a^3 + b^3 + 3ab (a + b)

Since a+b = 1, So now your equation in the end becomes..

(1-3ab)/3ab = 1/3ab - 1

I guess now theres no other way than to put the values & calculate

answer = 3.76
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by winnerhere » Sun May 17, 2009 10:25 am
Thanks brother. :)