diff --git a/basis/math/ranges/ranges-tests.factor b/basis/math/ranges/ranges-tests.factor
index 1f8b63bbab..a65ac20504 100644
--- a/basis/math/ranges/ranges-tests.factor
+++ b/basis/math/ranges/ranges-tests.factor
@@ -1,4 +1,4 @@
-USING: math math.ranges sequences sets tools.test arrays ;
+USING: arrays kernel math math.ranges sequences sets tools.test ;
 IN: math.ranges.tests
 
 [ { } ] [ 1 1 (a,b) >array ] unit-test
@@ -51,3 +51,8 @@ IN: math.ranges.tests
 [ 100 ] [
     1 100 [a,b] [ 2^ [1,b] ] map members length
 ] unit-test
+
+{ t } [ -10 10 1 <range> [ sum ] [ >array sum ] bi = ] unit-test
+{ t } [ -10 10 2 <range> [ sum ] [ >array sum ] bi = ] unit-test
+{ t } [ 10 -10 -1 <range> [ sum ] [ >array sum ] bi = ] unit-test
+{ t } [ 10 -10 -2 <range> [ sum ] [ >array sum ] bi = ] unit-test
diff --git a/basis/math/ranges/ranges.factor b/basis/math/ranges/ranges.factor
index d257a7dff2..4c63fd3f3c 100644
--- a/basis/math/ranges/ranges.factor
+++ b/basis/math/ranges/ranges.factor
@@ -32,6 +32,8 @@ M: range hashcode* tuple-hashcode ;
 
 INSTANCE: range immutable-sequence
 
+M: range sum [ length ] [ first ] [ last ] tri + * 2 / ;
+
 <PRIVATE
 
 : twiddle ( a b -- a b step ) 2dup > -1 1 ? ; inline