✅ Set interest to pay variable to 0

index.html

@@ -7,7 +7,7 @@
   }
 
   QUnit.test('$1 Loan Amount', (assert) => {
-    const interestToPay = undefined;
+    const interestToPay = 0;
     strictEqual({ expected: 0, actual: interestToPay }, assert);
   });
 </script>