diff --git a/src/main/c/main_taschenrechner.c b/src/main/c/main_taschenrechner.c
index 9727e18..cec5d6f 100644
--- a/src/main/c/main_taschenrechner.c
+++ b/src/main/c/main_taschenrechner.c
@@ -14,3 +14,7 @@ int add(int a, int b) {
 int minus (int a, int b){
     return a - b;
 }
+
+int multiply(int a, int b) {
+    return a * b;
+}
diff --git a/src/main/c/taschenrechner.h b/src/main/c/taschenrechner.h
index 0ebc004..e1ca752 100644
--- a/src/main/c/taschenrechner.h
+++ b/src/main/c/taschenrechner.h
@@ -5,4 +5,6 @@ int add(int a, int b);
 
 int minus(int a, int b);
 
+int multiply(int a, int b);
+
 #endif // TASCHENRECHNER_H