diff --git a/10_fibonacci/fibonacci.spec.js b/10_fibonacci/fibonacci.spec.js
index 7f62213..de632d8 100644
--- a/10_fibonacci/fibonacci.spec.js
+++ b/10_fibonacci/fibonacci.spec.js
@@ -16,9 +16,15 @@ describe('fibonacci', () => {
   test.skip('25th fibonacci number is 75025', () => {
     expect(fibonacci(25)).toBe(75025);
   });
+  test.skip('0th fibonacci number is 0', () => {
+    expect(fibonacci(0)).toBe(0);
+  });
   test.skip('doesn\'t accept negatives', () => {
     expect(fibonacci(-25)).toBe("OOPS");
   });
+  test.skip('DOES accept strings', () => {
+    expect(fibonacci("0")).toBe(0);
+  });
   test.skip('DOES accept strings', () => {
     expect(fibonacci("1")).toBe(1);
   });
diff --git a/10_fibonacci/solution/fibonacci-solution.js b/10_fibonacci/solution/fibonacci-solution.js
index acdd1e0..1327ce9 100644
--- a/10_fibonacci/solution/fibonacci-solution.js
+++ b/10_fibonacci/solution/fibonacci-solution.js
@@ -1,10 +1,19 @@
-const fibonacci = function(count) {
+const fibonacci = function(countArg) {
+    // checks argument's type and makes sure we use 
+    // a number throughout rest of function.
+    let count
+    if (typeof countArg !== 'number') {
+        count = parseInt(countArg)
+    } else {
+        count = countArg
+    }
+
     if (count < 0) return "OOPS";
-    if (count === 0) return 0;
+    if (count == 0) return 0;
 
     let firstPrev = 1;
     let secondPrev = 0;
-    
+
     for (let i = 2; i <= count; i++) {
         let current = firstPrev + secondPrev;
         secondPrev = firstPrev;
@@ -12,6 +21,14 @@ const fibonacci = function(count) {
     }
 
     return firstPrev;
+
 };
 
+// Another way to do it is by using an iterative approach with an array containing two values, 0 and 1.
+// const fib = [0, 1];
+// for (let i = 2; i <= count; i++) {
+//    fib[i] = fib[i - 1] + fib[i - 2];
+// }
+// return fib[count];
+
 module.exports = fibonacci;
diff --git a/10_fibonacci/solution/fibonacci-solution.spec.js b/10_fibonacci/solution/fibonacci-solution.spec.js
index 4e6a44d..fdb0bad 100644
--- a/10_fibonacci/solution/fibonacci-solution.spec.js
+++ b/10_fibonacci/solution/fibonacci-solution.spec.js
@@ -1,4 +1,4 @@
-const fibonacci = require('./fibonacci-solution');
+const fibonacci = require('./fibonacci-solution')
 
 describe('fibonacci', () => {
   test('4th fibonacci number is 3', () => {
@@ -16,19 +16,22 @@ describe('fibonacci', () => {
   test('25th fibonacci number is 75025', () => {
     expect(fibonacci(25)).toBe(75025);
   });
-  test('0th fibonacci number is o', () => {
+  test('0th fibonacci number is 0', () => {
     expect(fibonacci(0)).toBe(0);
   });
-  test("doesn't accept negatives", () => {
-    expect(fibonacci(-25)).toBe('OOPS');
+  test('doesn\'t accept negatives', () => {
+    expect(fibonacci(-25)).toBe("OOPS");
   });
   test('DOES accept strings', () => {
-    expect(fibonacci('1')).toBe(1);
+    expect(fibonacci("0")).toBe(0);
   });
   test('DOES accept strings', () => {
-    expect(fibonacci('2')).toBe(1);
+    expect(fibonacci("1")).toBe(1);
   });
   test('DOES accept strings', () => {
-    expect(fibonacci('8')).toBe(21);
+    expect(fibonacci("2")).toBe(1);
   });
-});
+  test('DOES accept strings', () => {
+    expect(fibonacci("8")).toBe(21);
+  });
+});
\ No newline at end of file