Question

For a normal curve, what percentage of values falls beyond two standard deviations from the mean?

Answer 1

I think you can easily get your answer here:

http://davidmlane.com/hyperstat/z_table.html

Answer 2

Read from the following table:

https://www.stat.tamu.edu/~lzhou/stat302/standardnormaltable.pdf

You will see that 2.275% of data falls beyond μ+2σ and another 2.275% of data falls below μ-2σ.