Problem calculating resistor wattage

[juz_ad]

I've been calculating the required wattage for some resistors in a circuit I'm simulating using:
1) V*I
2) (I^2)*R
3) (V^2)/R

I've noticed for some values the output of the equations don't match each other e.g.

V = 6.2
I = 0.0271 (27.1mA)
R = 47

Gives:
1) 0.168...
2) 0.034…
3) 0.817…

Why is this happening for some values and how can I 'fix' it?

Thanks.

 

[milan.rajik]

I = v / r = 0.1319148936170213


v * i = 0.8178723404255321

i^2 * r = 0.8178723404255322

v^2 / r = 0.8178723404255319

 

[juz_ad]

So it looks like the problem is my readings for I.

Thanks - appreciated.