diff --git a/python/currency-exchange/exchange.py b/python/currency-exchange/exchange.py
index 5880035..9503c18 100644
--- a/python/currency-exchange/exchange.py
+++ b/python/currency-exchange/exchange.py
@@ -72,9 +72,8 @@ def exchangeable_value(budget, exchange_rate, spread, denomination):
     :return: int - maximum value you can get.
     """
 
-    exchange = exchange_rate / 100
-    cost = exchange - spread
+    rate = exchange_rate + exchange_rate * spread / 100
+    new = exchange_money(budget, rate)
+    bill = get_number_of_bills(new, denomination)
 
-    result = budget - cost * denomination
-
-    return result
+    return get_value_of_bills(denomination, bill)