Last mathematical calculation you did?

[Kyng]

Splitting the bill at the restaurant I went to today.

(I was supposed to pay £23.00, while my friend was meant to pay £21.50... but we both ended up paying £22.25 anyway )

[Altair]

Splitting the bill at the restaurant I went to today.

(I was supposed to pay £23.00, while my friend was meant to pay £21.50... but we both ended up paying £22.25 anyway )

I always use to drive my ex boyfriend crazy with that. Everything had to be exactly even. 
-- 
I calculated 12 * 8
I could not remember what it was for the life of me. 
  
Now I can remember.

[Kyng]

Splitting the bill at the restaurant I went to today.

(I was supposed to pay £23.00, while my friend was meant to pay £21.50... but we both ended up paying £22.25 anyway )

I always use to drive my ex boyfriend crazy with that. Everything had to be exactly even. 

With me and my friends, we usually each pair for our own share... so I'm always the one who has to calculate everyone's bills !

[SpookyZalost]

Measuring the space for a desk expansion so I could have somewhere to put my 3D printer.

It's all sorts of cramped lol.

[Kyng]

Yeah, that does look cramped!

Myself, the last calculation I did was 0.35 x 3 = 1.05. (We bought three sachets of hot chocolate for £0.35 each 😛)

[Kyng]

1920/1440 = 4/3

I had to do that so that I knew the correct aspect ratio for a picture I was posting!

[Velocity Girl]

Converting 3800 GBP to IDR

[Kyng]

37 x 27 = 999

I did it by the "difference of two squares" method:
37 x 27 = (32 + 5)(32 - 5) = 32² - 5² = 1024 - 25 = 999

[Pyrite]

Using the good old ideal gas law to determine how much I needed to reduce the pressure of a particular gas in a sample I was prepping, in order to account for the change in temperature from 23°C to 0°C for this new measurement.

[Kyng]

Sounds more useful than most of my mathematical calculations !

In particular, the last one I did - which was √8^√2/√2^√8 = √2^√2 .

Proof

Start with:

√8^√2/√2^√8

Now, √8 = 2√2:

(2√2)^√2/√2^2√2

Now, use the rule (ab)^c = a^c b^c :

2^√2√2^√2/√2^2√2

Now, use the rule a^bc = (a^b)^c :

2^√2√2^√2/(√2²)^√2

Now, √2² = 2:

2^√2√2^√2/2^√2

Finally, cancel the 2^√2's:

√2^√2