Problem Solving

hi,

why does the cubic root of 0.000064 = 0.04

why does the square root of 0.04 = 0.2

I having difficultly in determining how many decimal place to move the answer after the cubic and sqaure roots are done, i.e. cubic root of 0.000064 = 0.04 and why not 0.004, etc.

thanks

When you multiply decimals together, the product will have as many digits to the right of the decimal as do the factors combined. For example,

.2 * .2 = .04

because the two factors each have 1 digit to the right of the decimal. Therefore, the product will have 1+1 = 2 digits to the right.

Similarly, .04*.04*.04 = .000064 because each of the 3 factors has 2 digits to the right of the decimal, so the product has 2+2+2 = 6 digits to the right.

I have a similar problem.
When I'm not sure, I just think of it as a regular multiplication (which it is anyway) and just count the # of decimal places in the number I'm multiplying.

So, for the cubic root of 0.000064 ==> 0.04.
when you multiply .04 by itself 3 times, you have to move the decimal 6 places to the left (2 decimal places in .04 * 3 times).

Likewise for the square root of 0.04 = 0.2, if you multiply that twice you get .04



I think this was the answer to your question