decimals and radicals

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decimals and radicals

by deltron » Mon Mar 29, 2010 6:46 am
I took the GMAT last week. I did pretty well, however, there were a few quant problems that I wasn't expecting.

I went through the Kaplan quiz bank and Manhattan GMAT practice tests. It seemed that on the real test, the questions were easier but the numbers they used were harder.

Two of the quant problems I saw had decimals under a radical. How do you handle that?

For example, what is √ (10^-10) ? what about √1.6 ?

Thanks
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by liferocks » Mon Mar 29, 2010 8:02 am
Hi,
In this case my approach is to take the decimal as fraction.ex 1.6=160/100(I took the denominator as 100 as this is a square number) then calculate square root of denominator and numerator finally divide to get the decimal.
Here is an article to calculate the square-root using algorithm.
https://www.homeschoolmath.net/teaching/ ... orithm.php
Hope this will help.

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by sakali » Mon Mar 29, 2010 1:19 pm
For Sqrt(10 ^-10)
you could take it as Sqrt (1/10^10)

which equals Sqrt(1) / 10^5