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kenewbie
Aug19-08, 02:11 PM
1. The problem statement, all variables and given/known data

Without using a calculator, find the solution to

\sqrt[3]{0.64 * 10^8}

3. The attempt at a solution

Well, I figure I want to get everything into powers of 3.

4^3 = 64, but that leaves 100 as the denominator to get 0.64, which does not play well with ^3.

I can split 10^8 into 10^3 * 10^3 * 10^2, but I dont see how that helps since I'm left with 10^2.

I can get to 100 * \sqrt[3]{0.64 * 10^2} which does give 400 (the correct answer).

So, what am I missing here?

k

kenewbie
Aug19-08, 02:16 PM
D'oh, finally saw it, sorry.

0.64 * 10^8 = 64 * 10^6, which makes the whole thing come together :)

k