diff --git a/src/core/include/mp-units/framework/quantity.h b/src/core/include/mp-units/framework/quantity.h
index 9933a760..d957cb14 100644
--- a/src/core/include/mp-units/framework/quantity.h
+++ b/src/core/include/mp-units/framework/quantity.h
@@ -448,7 +448,7 @@ public:
              }
   friend constexpr decltype(auto) operator*=(Q&& lhs, const Value& v)
   {
-    lhs.numerical_value_is_an_implementation_detail_ *= v;
+    lhs.numerical_value_is_an_implementation_detail_ = lhs.numerical_value_is_an_implementation_detail_ * v;
     return std::forward<Q>(lhs);
   }
 
@@ -461,7 +461,8 @@ public:
              }
   friend constexpr decltype(auto) operator*=(Q1&& lhs, const Q2& rhs)
   {
-    lhs.numerical_value_is_an_implementation_detail_ *= rhs.numerical_value_is_an_implementation_detail_;
+    lhs.numerical_value_is_an_implementation_detail_ = lhs.numerical_value_is_an_implementation_detail_ *
+                                                        rhs.numerical_value_is_an_implementation_detail_;
     return std::forward<Q1>(lhs);
   }
 
@@ -475,7 +476,7 @@ public:
   friend constexpr decltype(auto) operator/=(Q&& lhs, const Value& v)
   {
     MP_UNITS_EXPECTS_DEBUG(v != quantity_values<Value>::zero());
-    lhs.numerical_value_is_an_implementation_detail_ /= v;
+    lhs.numerical_value_is_an_implementation_detail_ = lhs.numerical_value_is_an_implementation_detail_ / v;
     return std::forward<Q>(lhs);
   }
 
@@ -489,7 +490,8 @@ public:
   friend constexpr decltype(auto) operator/=(Q1&& lhs, const Q2& rhs)
   {
     MP_UNITS_EXPECTS_DEBUG(rhs != rhs.zero());
-    lhs.numerical_value_is_an_implementation_detail_ /= rhs.numerical_value_is_an_implementation_detail_;
+    lhs.numerical_value_is_an_implementation_detail_ =  lhs.numerical_value_is_an_implementation_detail_ 
+                                                      / rhs.numerical_value_is_an_implementation_detail_;
     return std::forward<Q1>(lhs);
   }