Melody

Please use the calculator on the home page. 

$$\\1^3=1*1*1=1\\
2^3=2*2*2=8\\
3^3=3*3*3=27\\$$

1,8,27 are three cubic numbers.  

$$81^{1/4}\qquad $means$ \qquad \sqrt[4]{81}\\\\
\sqrt[4]{81}=3\qquad $because$ \qquad 3^4=3*3*3*3=81\\\\$$

Does that answer your question?

@@ End of Day Wrap     Sun 12/10/14 Sydney,     Sydney,  Australia Time 1:15am    (Really Mon morning)  ♬

Hello Everyone,

Today our fabulous answerers were Geno3141, Adamlightner17, Rosala, CPhill and Radio.  Thanks all.  

Here are a few interest posts:

1) Let's learn a little about Delhi.  Thank you Rosala.   

Mon 13/10/14

1) Light fun with numbers.

Well maybe one day I can come and you can show me around.  

And you can come to sydney and I will show you around too.  :)))

Sorry 315, besides the fact that it is late and my brain is shutting down.  My poor eyes really cannot read that. LOL

Yes I am Rosala, it is Monday.   

Mmm, let me see if I can remember this stuff.

sigma=6

so 81 is more than 3 standard deviations below the mean.

so p(X>=81)>99.7%

If you need more precision you can work out the z score 

Z=(81-100)/6=-3.1666666

then look up a z score table to find the associated area.  The tables are slighly diff and I don't know which version you are using.   I used this one.

I'm a little tired, it is nearly 1am, but otherwise I am doing very well thank you.