diff --git a/doc/scala/SparkUI.ipynb b/doc/scala/SparkUI.ipynb
index f29f48785f..10073f04f0 100644
--- a/doc/scala/SparkUI.ipynb
+++ b/doc/scala/SparkUI.ipynb
@@ -109,14 +109,14 @@
    "outputs": [],
    "source": [
     "val NUM_SAMPLES = 10000000\n",
-    "\n",
-    "val count2 = spark.sparkContext.parallelize(1 to NUM_SAMPLES).map{i =>\n",
-    "  val x = Math.random()\n",
-    "  val y = Math.random()\n",
+    "val random = new scala.util.Random()\n",
+    "val count = spark.sparkContext.parallelize(1 to NUM_SAMPLES).map{i =>\n",
+    "  val x = random.nextDouble()\n",
+    "  val y = random.nextDouble()\n",
     "  if (x*x + y*y < 1) 1 else 0\n",
     "}.reduce(_ + _)\n",
     "\n",
-    "println(\"Pi is roughly \" + 4.0 * count2 / NUM_SAMPLES)"
+    "println(\"Pi is roughly \" + 4.0 * count / NUM_SAMPLES)"
    ]
   },
   {