diff --git a/coroutines-guide.md b/coroutines-guide.md
index 64af574..4681f88 100644
--- a/coroutines-guide.md
+++ b/coroutines-guide.md
@@ -353,12 +353,13 @@
 
 ```kotlin
 fun main(args: Array<String>) = runBlocking<Unit> {
+    val startTime = System.currentTimeMillis()
     val job = launch(CommonPool) {
-        var nextPrintTime = System.currentTimeMillis()
+        var nextPrintTime = startTime
         var i = 0
-        while (i < 10) { // computation loop
-            val currentTime = System.currentTimeMillis()
-            if (currentTime >= nextPrintTime) {
+        while (i < 10) { // computation loop, just wastes CPU
+            // print a message twice a second
+            if (System.currentTimeMillis() >= nextPrintTime) {
                 println("I'm sleeping ${i++} ...")
                 nextPrintTime += 500L
             }
@@ -393,18 +394,19 @@
 invoke a suspending function. There is a [yield] function that is a good choice for that purpose.
 The other one is to explicitly check the cancellation status. Let us try the later approach. 
 
-Replace `while (true)` in the previous example with `while (isActive)` and rerun it. 
+Replace `while (i < 10)` in the previous example with `while (isActive)` and rerun it. 
 
 ```kotlin
 fun main(args: Array<String>) = runBlocking<Unit> {
+    val startTime = System.currentTimeMillis()
     val job = launch(CommonPool) {
-        var nextPrintTime = 0L
+        var nextPrintTime = startTime
         var i = 0
         while (isActive) { // cancellable computation loop
-            val currentTime = System.currentTimeMillis()
-            if (currentTime >= nextPrintTime) {
+            // print a message twice a second
+            if (System.currentTimeMillis() >= nextPrintTime) {
                 println("I'm sleeping ${i++} ...")
-                nextPrintTime = currentTime + 500L
+                nextPrintTime += 500L
             }
         }
     }
diff --git a/kotlinx-coroutines-core/src/test/kotlin/guide/example-cancel-02.kt b/kotlinx-coroutines-core/src/test/kotlin/guide/example-cancel-02.kt
index b79d525..1e99b34 100644
--- a/kotlinx-coroutines-core/src/test/kotlin/guide/example-cancel-02.kt
+++ b/kotlinx-coroutines-core/src/test/kotlin/guide/example-cancel-02.kt
@@ -20,12 +20,13 @@
 import kotlinx.coroutines.experimental.*
 
 fun main(args: Array<String>) = runBlocking<Unit> {
+    val startTime = System.currentTimeMillis()
     val job = launch(CommonPool) {
-        var nextPrintTime = System.currentTimeMillis()
+        var nextPrintTime = startTime
         var i = 0
-        while (i < 10) { // computation loop
-            val currentTime = System.currentTimeMillis()
-            if (currentTime >= nextPrintTime) {
+        while (i < 10) { // computation loop, just wastes CPU
+            // print a message twice a second
+            if (System.currentTimeMillis() >= nextPrintTime) {
                 println("I'm sleeping ${i++} ...")
                 nextPrintTime += 500L
             }
diff --git a/kotlinx-coroutines-core/src/test/kotlin/guide/example-cancel-03.kt b/kotlinx-coroutines-core/src/test/kotlin/guide/example-cancel-03.kt
index 619b6b7..8746d38 100644
--- a/kotlinx-coroutines-core/src/test/kotlin/guide/example-cancel-03.kt
+++ b/kotlinx-coroutines-core/src/test/kotlin/guide/example-cancel-03.kt
@@ -20,14 +20,15 @@
 import kotlinx.coroutines.experimental.*
 
 fun main(args: Array<String>) = runBlocking<Unit> {
+    val startTime = System.currentTimeMillis()
     val job = launch(CommonPool) {
-        var nextPrintTime = 0L
+        var nextPrintTime = startTime
         var i = 0
         while (isActive) { // cancellable computation loop
-            val currentTime = System.currentTimeMillis()
-            if (currentTime >= nextPrintTime) {
+            // print a message twice a second
+            if (System.currentTimeMillis() >= nextPrintTime) {
                 println("I'm sleeping ${i++} ...")
-                nextPrintTime = currentTime + 500L
+                nextPrintTime += 500L
             }
         }
     }