diff --git a/05_sumAll/sumAll.js b/05_sumAll/sumAll.js
index 210720e..a6b356e 100644
--- a/05_sumAll/sumAll.js
+++ b/05_sumAll/sumAll.js
@@ -1,11 +1,27 @@
 const sumAll = function(num1, num2) {
     let sum = 0;
-            
-    for (let i = num1; i <= num2; i++) {
-        sum += parseInt(i);
-    }
+    let num1Type = typeof num1;
+    let num2Type = typeof num2;
 
-    return sum;
+    //Ensures number is not negative
+    if (num1 < 0 || num2 < 0) {
+        return "ERROR";
+    //Ensures sum is a number
+    } else if (num1Type !== "number" || num2Type !== "number") {
+        return "ERROR";
+    //If the second number is smaller than the first number
+    } else if (num2 < num1) {
+        for (let i = num2; i <= num1; i++) {
+            sum += parseInt(i);
+        }
+        return sum;
+    //If the first number is larger than the second number
+    } else {
+        for (let i = num1; i <= num2; i++) {
+            sum += parseInt(i);
+        }
+        return sum;
+    }
 };
 
 // Do not edit below this line
diff --git a/05_sumAll/sumAll.spec.js b/05_sumAll/sumAll.spec.js
index 1a9fb7c..a171e5f 100644
--- a/05_sumAll/sumAll.spec.js
+++ b/05_sumAll/sumAll.spec.js
@@ -4,19 +4,19 @@ describe('sumAll', () => {
   test('sums numbers within the range', () => {
     expect(sumAll(1, 4)).toEqual(10);
   });
-  test.skip('works with large numbers', () => {
+  test('works with large numbers', () => {
     expect(sumAll(1, 4000)).toEqual(8002000);
   });
-  test.skip('works with larger number first', () => {
+  test('works with larger number first', () => {
     expect(sumAll(123, 1)).toEqual(7626);
   });
-  test.skip('returns ERROR with negative numbers', () => {
+  test('returns ERROR with negative numbers', () => {
     expect(sumAll(-10, 4)).toEqual('ERROR');
   });
-  test.skip('returns ERROR with non-number parameters', () => {
+  test('returns ERROR with non-number parameters', () => {
     expect(sumAll(10, "90")).toEqual('ERROR');
   });
-  test.skip('returns ERROR with non-number parameters', () => {
+  test('returns ERROR with non-number parameters', () => {
     expect(sumAll(10, [90, 1])).toEqual('ERROR');
   });
 });