diff --git a/extra/1-factorial.js b/extra/1-factorial.js
index da9f8e6c..e0fb2e3c 100644
--- a/extra/1-factorial.js
+++ b/extra/1-factorial.js
@@ -9,7 +9,12 @@
 */
 
 function factorial(input) {
-  // TODO
+  let result = 1;
+
+  for(let i=2; i <= input; i++) {
+    result *= i
+  }
+  return result;
 }
 
 /* ======= TESTS - DO NOT MODIFY ===== */
diff --git a/mandatory/1-fix-functions.js b/mandatory/1-fix-functions.js
index 6323604f..a50ac997 100644
--- a/mandatory/1-fix-functions.js
+++ b/mandatory/1-fix-functions.js
@@ -10,10 +10,8 @@
 
 */
 
-function getMood() {
-  let isHappy = true;
-
-  if (isHappy) {
+function getMood(happy) {
+  if (happy) {
     return "I am happy";
   } else {
     return "I am not happy";
@@ -21,9 +19,7 @@ function getMood() {
 }
 
 function greaterThan10(num) {
-  let isBigEnough;
-
-  if (isBigEnough) {
+  if (num > 10) {
     return "num is greater than 10";
   } else {
     return "num is not big enough";
diff --git a/mandatory/2-function-creation.js b/mandatory/2-function-creation.js
index d4590920..b3e45bcc 100644
--- a/mandatory/2-function-creation.js
+++ b/mandatory/2-function-creation.js
@@ -4,8 +4,16 @@
     1. the user should be 18 or older
     2. the user must be logged in
 */
-function isAcceptableUser(userAge, isLoggedIn) {}
-
+function isAcceptableUser(userAge, isLoggedIn) {
+
+  if (userAge >= 18 && isLoggedIn === true ){
+    return true;
+  } else if (userAge > 18 && isLoggedIn === true) {
+    return false;
+  } else {
+    return false;
+  }
+}
 /*
   Complete the function to apply discount percent based on how much is totalPrice in user cart.
     - When the total price is greater than 200, a 10% discount should be applied
@@ -15,18 +23,39 @@ function isAcceptableUser(userAge, isLoggedIn) {}
     is applieds and 142.5 should be returned)
 */
 
-function applyDiscount(totalPrice) {}
+function applyDiscount(totalPrice) {
+  if (totalPrice > 200) {
+    return totalPrice * 0.9;
+  } else if ( totalPrice < 200) {
+    return totalPrice * 0.95;
+  }
+}
 
 /*
   Complete the function to print to the console the odd numbers between 1 and limit (use a while loop):
   */
-function printOddNumbers(limit) {}
+function printOddNumbers(limit) {
+  for (let i = 1; i <= limit; i++) {
+    if (i % 2 === 1) {
+      console.log(i);
+    }
+  }
+}
 
 /*
   Complete the buyTwoGetTheCheapestFree function: if user buys two items, the cheapest item will be free!
   The function should return the price to be paid once the discount is applied.
 */
-function buyTwoGetTheCheapestFree(price1, price2) {}
+function buyTwoGetTheCheapestFree(price1, price2) {
+  if (price1 <= 0 || price2 <= 0) {
+    return "Invalid prices. Prices must be more than 0.";
+  }
+  if (price1 >= price2) {
+    return price1;
+  } else {
+    return price2;
+  }
+}
 
 /*
   Complete the function to determine if it is suitable for a person to register based on their age!
@@ -34,7 +63,15 @@ function buyTwoGetTheCheapestFree(price1, price2) {}
   - if the person is older than 12 and younger than 90 it should return "You Can Register"
   - if the person is 90 or older it should return "You Don't Need To Register"
 */
-function canRegister(age) {}
+function canRegister(age) {
+  if (age <= 12) {
+    return "You Are Too Young To Register"
+  } else if (age > 12 && age < 90) {
+    return"You Can Register"
+  }else if (age >= 90) {
+    return "You Don't Need To Register"
+  }
+}
 
 /*
   Complete the function so that it prints out to the console numbers in reverse order starting at
@@ -45,7 +82,11 @@ function canRegister(age) {}
   )
 */
 
-function countReverse(number) {}
+function countReverse(number) {
+  for (let i = number; i >= 1; i--) {
+    console.log(i);
+  }
+}
 
 /* ======= TESTS - DO NOT MODIFY ===== */