diff --git a/activesupport/test/notifications_test.rb b/activesupport/test/notifications_test.rb
index 3e16e01d89a1f161ec2bde7887a06e1cbafca691..73c85be87c2f0a2df72a71670ce8990d9d198be6 100644
--- a/activesupport/test/notifications_test.rb
+++ b/activesupport/test/notifications_test.rb
@@ -200,7 +200,7 @@ def test_events_are_initialized_with_details
 
       assert_equal    :foo, event.name
       assert_equal    time, event.time
-      assert_in_delta 10.0, event.duration, 0.00000000000001
+      assert_in_delta 10.0, event.duration, 0.00001
     end
 
     def test_events_consumes_information_given_as_payload