Add Euro symbol or the letters EUR to the left of dollar amount in a formula

The type on the formula variable was incorrect

var number PriceToUse = Case([Price List to Use],
"US List Price", [US List Price],
"Asia Dist Price", [Asia Dist Price],
"Asia List Price", [Asia List Price],
"EUR Dist Price", [EU Dist Price],
"EUR List Price",  [EU List Price]);