diff --git a/LibTest/async/Timer/Timer.periodic_A01_t01.dart b/LibTest/async/Timer/Timer.periodic_A01_t01.dart
index 5560e7a173..943264cad2 100644
--- a/LibTest/async/Timer/Timer.periodic_A01_t01.dart
+++ b/LibTest/async/Timer/Timer.periodic_A01_t01.dart
@@ -46,7 +46,7 @@ main() {
     Duration expected = delay * count;
     Duration actual = sw.elapsed;
     Expect.isTrue(expected <= actual + safetyMargin,
-        "expected=$expected, actual=${actual + safetyMargin}");
+        "expected=$expected, actual=$actual");
     if (count == maxCount) {
       timer.cancel();
       asyncEnd();
diff --git a/LibTest/async/Timer/Timer.periodic_A02_t02.dart b/LibTest/async/Timer/Timer.periodic_A02_t02.dart
index 848d0b5946..2be13e7761 100644
--- a/LibTest/async/Timer/Timer.periodic_A02_t02.dart
+++ b/LibTest/async/Timer/Timer.periodic_A02_t02.dart
@@ -8,7 +8,7 @@
 /// A negative duration is treated the same as [Duration.zero]
 ///
 /// @description Checks that negative duration is accepted and treated as
-/// [Duration.zero]. Test that timer waits for microtasks queue before
+/// [Duration.zero]. Test that timer waits for microtask queue before
 /// triggering
 /// @author sgrekhov22@gmail.com
 
diff --git a/LibTest/async/Timer/Timer_A01_t01.dart b/LibTest/async/Timer/Timer_A01_t01.dart
index ee46018794..a61b725542 100644
--- a/LibTest/async/Timer/Timer_A01_t01.dart
+++ b/LibTest/async/Timer/Timer_A01_t01.dart
@@ -27,7 +27,7 @@ check(int delayms) {
   new Timer(delay, () {
     Duration actual = sw.elapsed;
     Expect.isTrue(delay <= actual + safetyMargin,
-        "expected=$delay, actual=${actual + safetyMargin}");
+        "expected=$delay, actual=$actual");
     asyncEnd();
   });
 }