diff --git a/solutions/tests/test_binary_decimal_conversion.py b/solutions/tests/test_binary_decimal_conversion.py
index 9a730e226..9f0de303d 100644
--- a/solutions/tests/test_binary_decimal_conversion.py
+++ b/solutions/tests/test_binary_decimal_conversion.py
@@ -18,6 +18,8 @@
 
 
 class TestBinaryDecimalConversion(unittest.TestCase):
+    """Tests for binaru_decimal_conversion function"""
+
     def test_decimal_to_binary(self):
         """Should convert positive decimal numbers to binary"""
         self.assertEqual(decimal_to_binary(10), "1010")
@@ -32,7 +34,7 @@ def test_zero_decimal_to_binary(self):
 
     def test_zero_binary_to_decimal(self):
         """should return 0"""
-        self.assertEqual(binary_to_decimal(0), "0")
+        self.assertEqual(binary_to_decimal("0"), "0")
 
     def test_large_decimal_to_binary(self):
         """Should correctly handle large decimal numbers"""