diff --git a/src/test/c/test_taschenrechner.c b/src/test/c/test_taschenrechner.c
index 39414dd..f51aaad 100644
--- a/src/test/c/test_taschenrechner.c
+++ b/src/test/c/test_taschenrechner.c
@@ -156,52 +156,4 @@ void test_exponentialFunction(void) {
     TEST_ASSERT_EQUAL_FLOAT(1.0, exponentialFunction(0.0));
 }
 
-// addition with two numbers
-void test_performOperation_Addition(void) {
-    // Arrange
-    int result;
-
-    // Act
-    result = performOperation(5, '+', 3);
-
-    // Assert
-    TEST_ASSERT_EQUAL_INT(8, result);
-}
-
-// Test case for subtraction
-void test_performOperation_Subtraction(void) {
-    // Arrange
-    int result;
-
-    // Act
-    result = performOperation(10, '-', 3);
-
-    // Assert
-    TEST_ASSERT_EQUAL_INT(7, result);
-}
-
-// Test case for multiplication
-void test_performOperation_Multiplication(void) {
-    // Arrange
-    int result;
-
-    // Act
-    result = performOperation(4, '*', 6);
-
-    // Assert
-    TEST_ASSERT_EQUAL_INT(24, result);
-}
-
-// Test case for division
-void test_performOperation_Division(void) {
-    // Arrange
-    int result;
-
-    // Act
-    result = performOperation(8, '/', 2);
-
-    // Assert
-    TEST_ASSERT_EQUAL_INT(4, result);
-}
-
 #endif // TEST