diff --git a/CM2005 Object Oriented Programming/Topic 5/5.1.9/Wallet.cpp b/CM2005 Object Oriented Programming/Topic 5/5.1.9/Wallet.cpp
index 474c6c8..48ebbd0 100644
--- a/CM2005 Object Oriented Programming/Topic 5/5.1.9/Wallet.cpp	
+++ b/CM2005 Object Oriented Programming/Topic 5/5.1.9/Wallet.cpp	
@@ -24,6 +24,29 @@ void Wallet::insertCurrency(std::string type, double amount)
   currencies[type] = balance;
 }
 
+bool Wallet::removeCurrency(std::string type, double amount)
+{
+  double balance;
+  if(amount < 0)
+  {
+    return false;
+  }
+  if(currencies.count(type) == 0) // currency not in wallet
+  {
+    return false;
+  }
+  else // is there, do we have enough?
+  {
+    if(containsCurrency(type, amount))
+    {
+      currencies[type] -= amount;
+      return true;
+    }
+    else // didn't have enough
+      return false;
+  }
+}
+
 bool Wallet::containsCurrency(std::string type, double amount)
 {
   if(currencies.count(type) == 0) // not in wallet yet
@@ -44,4 +67,4 @@ std::string Wallet::toString()
     s += currency + " : " + std::to_string(amount) + "\n";
   }
   return s;
-}
\ No newline at end of file
+}
diff --git a/CM2005 Object Oriented Programming/Topic 5/5.1.9/Wallet.h b/CM2005 Object Oriented Programming/Topic 5/5.1.9/Wallet.h
index 3c68252..b147aae 100644
--- a/CM2005 Object Oriented Programming/Topic 5/5.1.9/Wallet.h	
+++ b/CM2005 Object Oriented Programming/Topic 5/5.1.9/Wallet.h	
@@ -10,6 +10,9 @@ class Wallet
     /** insert currency to the wallet */
     void insertCurrency(std::string type, double amount);
 
+    /** remove currency from the wallet */
+    bool removeCurrency(std::string type, double amount);
+
     /** check if the wallet contains at least this much currency */
     bool containsCurrency(std::string type, double amount);
 
diff --git a/CM2005 Object Oriented Programming/Topic 5/5.1.9/a.exe b/CM2005 Object Oriented Programming/Topic 5/5.1.9/a.exe
index d08a97e..e7a47ed 100644
Binary files a/CM2005 Object Oriented Programming/Topic 5/5.1.9/a.exe and b/CM2005 Object Oriented Programming/Topic 5/5.1.9/a.exe differ
diff --git a/CM2005 Object Oriented Programming/Topic 5/5.1.9/main.cpp b/CM2005 Object Oriented Programming/Topic 5/5.1.9/main.cpp
index 45cbe4e..303e1e5 100644
--- a/CM2005 Object Oriented Programming/Topic 5/5.1.9/main.cpp	
+++ b/CM2005 Object Oriented Programming/Topic 5/5.1.9/main.cpp	
@@ -13,7 +13,9 @@ int main()
     Wallet wallet;
     wallet.insertCurrency("BTC", 10);
     wallet.insertCurrency("USDT", 100.83);
-    std::cout << "Wallet has BTC " << wallet.containsCurrency("USDT", 100.50) << std::endl;
+    std::cout << wallet.toString() << std::endl;
+    //std::cout << "Wallet has BTC " << wallet.containsCurrency("USDT", 100.50) << std::endl;
+    wallet.removeCurrency("USDT", 10);
     std::cout << wallet.toString() << std::endl;
     //CSVReader::readCSV("20200317.csv");