Currency Position Configuration in Magento

You can observe currency_display_options_forming event dispatched in Mage_Core_Model_Locale class

<currency_display_options_forming>
    <observers>
        <foo_bar>
            <class>foo_bar/observer</class>
            <method>currencyDisplayOptionsForming</method>
        </foo_bar>
    </observers>
</currency_display_options_forming>

Observer:

class Foo_Bar_Model_Observer
{
    public function currencyDisplayOptionsForming(Varien_Event_Observer $observer)
    {
        if (Mage::app()->getLocale()->getLocaleCode() == 'en_US' &&
            Mage::app()->getStore()->getCurrentCurrency()->getCode() == 'EUR'
        ) {
            $options = $observer->getEvent()->getCurrencyOptions();
            $options['position'] = Zend_Currency::RIGHT;
        }

        return $this;
    }
}

Look in Zend_Currency class for additional options.

Finally, issue solved. it was with currency rate.

Admin ==> Stores ==> Currency Rates

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