Answer: 0.1 assuming my 2 SCI calculators and my manual calculations are correct Comments: 1- 0.3167 is the square-root of 0.1 not 0.01 2- Don't tell you interviewer he is wrong. You want the job don't you? 3- You actually need to use a 5/4 round-off using the 5th place for a more accurate 4th ( I think that's what you meant to say)

I think you mean the sqrt of 0.1, not 0.01. The sqrt of 0.01 is 0.1.

0.01 is the same as 1/100 and if you take the square root of the top and bottom, you get 1/10 or 0.1.

actually, square roots are always positive. the definition of a square root is that it's an absolute value. i.e. sqrt of (-1)*(-1) = |-1| = 1 My real response to this topic though is that I dread such silliness in interviews. In my current position I was asked a stupid question in a 5-on-1 interview and basically said what I thought about the question but still got the job - so maybe that was the correct answer. Hope I don't ever find myself desperately needing a job and having to endure this silliness again.

Isn't it prime already? So its sq rt is 0.01. I'm so confused!

Not to be a fuddy-duddy, but .3162 would be closer. (If you're going to take it to 4 decimals then you should use the closest 4th decimal.)

.3167 - Just memorize it, it's very common.