diff --git a/tests/bonsai/rpn.mk b/tests/bonsai/rpn.mk
index 2ac1243..3619692 100755
--- a/tests/bonsai/rpn.mk
+++ b/tests/bonsai/rpn.mk
@@ -6,7 +6,7 @@
 # notice are preserved.  This file is offered as-is, without any warranty.
 
 .PHONY: rpn_tests
-rpn_tests: rpn_help rpn_add
+rpn_tests: rpn_help rpn_add rpn_sub rpn_mul rpn_div rpn_mod rpn_flr
 
 .PHONY: rpn_help
 rpn_help: $(BIN)/rpn
@@ -20,7 +20,7 @@ rpn_add: $(BIN)/rpn
 .PHONY: rpn_sub
 rpn_sub: $(BIN)/rpn
 	test "$$($(BIN)/rpn 23 5 -)" -eq 18
-	test "$$($(BIN)/rpn 0.3 0.1)" = 0.2
+	test "$$($(BIN)/rpn 0.3 0.1 -)" = 0.2
 
 .PHONY: rpn_mul
 rpn_mul: $(BIN)/rpn