American $ - Euros - American $

Sorry if it's in the wrong section, didn't know where to put it.

Anyways,
I want to learn how to convert American $ (1.20$) to Euros (€). And Vise versa meaning (Euro - American $)

IS there a easy way to convert it without a calculator or the internet?
Pencil and paper is okay, but I don't want a method that uses a calculator.
Also, please make sure before you post that the converting is correct lol.
I'll make sure as well.
Signs: Euro- € Am.- $
Thanks. c:
Don't quote the whole thread pls, just tag me or reply. I dislike it when people quote the whole thing.

 

1 USD = 0.81 Euros.
With that you should be able to calculate all prices,

 

What about when the market changes?
It isn't always a correct calculate.
With that, just check up on the thing every now and again, and just estimate. :P
I estimate AUD-USD and vice versa.
$100 AUD is ~$90 USD
$100 USD is ~$110 AUD
There's a 10 cent difference between the currencies.

 

U mean dollars?

 

Yea, I think that's what she meant.
Though I didn't notice lol.

 

No.
I meant currencies.
Maybe google it.