diff --git a/test/intl402/Locale/constructor-options-numeric-undefined.js b/test/intl402/Locale/constructor-options-numeric-undefined.js
new file mode 100644
index 0000000000..e125b53302
--- /dev/null
+++ b/test/intl402/Locale/constructor-options-numeric-undefined.js
@@ -0,0 +1,53 @@
+// Copyright 2018 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-intl.locale
+description: Verifies the behavior of an undefined numeric option to the Locale constructor.
+info: |
+    Intl.Locale( tag [, options] )
+
+    ...
+    24. Let kn be ? GetOption(options, "numeric", "boolean", undefined, undefined).
+    25. If kn is not undefined, set kn to ! ToString(kn).
+    ...
+    30. Let r be ! ApplyUnicodeExtensionToTag(tag, opt, relevantExtensionKeys).
+    ...
+
+    ApplyUnicodeExtensionToTag( tag, options, relevantExtensionKeys )
+
+    ...
+    8. Let locale be the String value that is tag with all Unicode locale extension sequences removed.
+    9. Let newExtension be ! CanonicalizeUnicodeExtension(attributes, keywords).
+    10. If newExtension is not the empty String, then
+        a. Let locale be ! InsertUnicodeExtension(locale, newExtension).
+    ...
+
+    CanonicalizeUnicodeExtension( attributes, keywords )
+    ...
+    4. Repeat for each element entry of keywords in List order,
+        a. Let keyword be entry.[[Key]].
+        b. If entry.[[Value]] is not the empty String, then
+            i. Let keyword be the string-concatenation of keyword, "-", and entry.[[Value]].
+        c. Append keyword to fullKeywords.
+    ...
+features: [Intl.Locale]
+---*/
+
+const options = { numeric: undefined };
+assert.sameValue(
+  new Intl.Locale('en', options).toString(),
+  "en",
+);
+
+assert.sameValue(
+  new Intl.Locale('en-u-kn-true', options).toString(),
+  "en-u-kn-true",
+);
+
+if ("numeric" in Intl.Locale.prototype) {
+  assert.sameValue(
+    new Intl.Locale('en-u-kf-lower', options).numeric,
+    undefined,
+  );
+}
diff --git a/test/intl402/Locale/constructor-options-numeric-valid.js b/test/intl402/Locale/constructor-options-numeric-valid.js
index 50880232a0..a954466813 100644
--- a/test/intl402/Locale/constructor-options-numeric-valid.js
+++ b/test/intl402/Locale/constructor-options-numeric-valid.js
@@ -36,24 +36,25 @@ features: [Intl.Locale]
 ---*/
 
 const validNumericOptions = [
-  [undefined, undefined],
-  [false, "false"],
-  [true, "true"],
-  [null, "false"],
-  [0, "false"],
-  [0.5, "true"],
-  [{ valueOf() { return false; } }, "true"],
+  [false, false],
+  [true, true],
+  [null, false],
+  [0, false],
+  [0.5, true],
+  ["true", true],
+  ["false", true],
+  [{ valueOf() { return false; } }, true],
 ];
 for (const [numeric, expected] of validNumericOptions) {
   const options = { numeric };
   assert.sameValue(
     new Intl.Locale('en', options).toString(),
-    expected ? ("en-u-kn-" + expected) : "en"
+    "en-u-kn-" + expected
   );
 
   assert.sameValue(
     new Intl.Locale('en-u-kn-true', options).toString(),
-    "en-u-kn-" + (expected || "true")
+    "en-u-kn-" + expected
   );
 
   if ("numeric" in Intl.Locale.prototype) {