When we are dealing with multiple currencies we need to configure those rate correctly in system.
To do, first make sure you have multiple currency activated(To activate Go to Accounting > Setting under Accounting & Finance find out “Allow multi currencies” and activate it)
After Activate go to debug mode (To do this click on your Username in the top right of the backend (in my case it was ‘Administrator’) then click on About and then Activate the Developer mode)
Now, you can see new menu added in Accounting > Configuration > Multi Currencies. You can see list of currencies, now first of all find out your company currency and set currency rate 1.0. now for the rest of currencies find out currency rate against your company currency and add it(If you have enterprise version then you can use auto update currency rate using yahoo finance,…).
Ex. My company currency INR, so i change current rate of INR to 1.0 and for rest of currency like EUR, USD i can set rate against INR means
1 INR = ? EUR, 1 INR = ? USD .