--- a/RegressionTests__TimeDurationTest.st	Thu May 10 13:02:58 2018 +0200
+++ b/RegressionTests__TimeDurationTest.st	Thu May 10 14:25:34 2018 +0200
@@ -77,7 +77,7 @@
     "
 !
 
-test_01_Arithmetic
+test_01_Addition
     |t1 t2 sum|
 
     t1 := TimeDuration fromSeconds:1.
@@ -108,11 +108,11 @@
 
 
     "
-     self new test_01_Arithmetic
+     self new test_01_Addition
     "
 !
 
-test_02_Arithmetic
+test_02_Subtraction
     |t1 t2 sum|
 
     t1 := TimeDuration fromSeconds:1.
@@ -143,7 +143,135 @@
 
 
     "
-     self new test_01_Arithmetic
+     self new test_01_Subtraction
+    "
+!
+
+test_03_Multiplication
+    |t rslt|
+
+    t := TimeDuration fromSeconds:1.
+    rslt := t * 5.
+    self assert:(rslt asMilliseconds == 5000).
+    self assert:(rslt asPicoseconds = 5000000000000).
+
+    rslt := 5 * t.
+    self assert:(rslt asMilliseconds == 5000).
+    self assert:(rslt asPicoseconds = 5000000000000).
+
+
+    t := TimeDuration fromSeconds:1.1.
+    rslt := t * 2.
+    self assert:(rslt asMilliseconds == 2200).
+    self assert:(rslt asPicoseconds = 2200000000000).
+
+    rslt := 2 * t.
+    self assert:(rslt asMilliseconds == 2200).
+    self assert:(rslt asPicoseconds = 2200000000000).
+
+
+    t := TimeDuration fromNanoseconds:100.
+    rslt := t * 4.5.
+    self assert:(rslt asNanoseconds = 450).
+    self assert:(rslt asPicoseconds = 450000).
+
+    rslt := 4.5 * t.
+    self assert:(rslt asNanoseconds = 450).
+    self assert:(rslt asPicoseconds = 450000).
+
+
+    t := TimeDuration fromMilliseconds:100.
+    t := t + 50 nanoseconds.
+
+    rslt := t * 5.
+    self assert:(rslt asNanoseconds = 500000250).
+
+    rslt := 5 * t.
+    self assert:(rslt asNanoseconds = 500000250).
+
+
+    "
+     self new test_03_Multiplication
+    "
+!
+
+test_04_Division
+    |t rslt|
+
+    t := TimeDuration fromSeconds:1.
+    rslt := t / 5.
+    self assert:(rslt asMilliseconds == 200).
+    self assert:(rslt asPicoseconds = 200000000000).
+
+
+    t := TimeDuration fromSeconds:2.2.
+    rslt := t / 2.
+    self assert:(rslt asMilliseconds == 1100).
+    self assert:(rslt asPicoseconds = 1100000000000).
+
+
+    t := TimeDuration fromNanoseconds:450.
+    rslt := t / 4.5.
+    self assert:(rslt asNanoseconds = 100).
+    self assert:(rslt asPicoseconds = 100000).
+
+
+    t := TimeDuration fromMilliseconds:100.
+    t := t + 50 nanoseconds.
+
+    rslt := t / 5.
+    self assert:(rslt asNanoseconds = 20000010).
+
+
+    "
+     self new test_04_Division
+    "
+!
+
+test_05_Division    
+    "dividing two timeDurations gives a numeric quotient"
+
+    |t1 t2 rslt|
+
+    t1 := TimeDuration fromSeconds:1.
+    t2 := TimeDuration fromSeconds:2.
+    rslt := t1 / t2.
+    self assert:(rslt isNumber).
+    self assert:(rslt = 0.5).
+
+    t1 := TimeDuration fromSeconds:1.
+    t2 := TimeDuration fromMilliseconds:1.
+    rslt := t1 / t2.
+    self assert:(rslt isNumber).
+    self assert:(rslt = 1000).
+
+    t1 := TimeDuration fromMilliseconds:1.
+    t2 := TimeDuration fromMicroseconds:1.
+    rslt := t1 / t2.
+    self assert:(rslt isNumber).
+    self assert:(rslt = 1000).
+
+    t1 := TimeDuration fromMicroseconds:1.
+    t2 := TimeDuration fromNanoseconds:1.
+    rslt := t1 / t2.
+    self assert:(rslt isNumber).
+    self assert:(rslt = 1000).
+
+    t1 := TimeDuration fromSeconds:1.
+    t2 := TimeDuration fromNanoseconds:1.
+    rslt := t1 / t2.
+    self assert:(rslt isNumber).
+    self assert:(rslt = 1000000000).
+
+    t1 := TimeDuration fromSeconds:1.
+    t2 := TimeDuration fromNanoseconds:50.
+    rslt := t1 / t2.
+    self assert:(rslt isNumber).
+    self assert:(rslt = 20000000).
+
+
+    "
+     self new test_05_Division
     "
 !