by RonPurewal Wed Oct 24, 2007 5:27 am
All of the following statements are for cases where the given decimals are perfect squares / cubes / whatever. If not, then the roots are nonterminating decimals (which you are extremely unlikely to have to deal with on this test).
* The square root of a decimal will have half as many decimal places as does the original decimal.
* The cube root of a decimal will have one-third as many decimal places as does the original decimal.
Etc.
So 0.000064 has six decimal places, meaning that the cube root will have two decimal places, so it's 0.04. Note that you have to recognize that 4 is the cube root of 64 (I think our strategy guides tell you to memorize the perfect cubes of the first few integers).
Incidentally, you could just try cubing different decimals ending with '4' and see which one hits the jackpot. It shouldn't take that long.