diff --git a/src/extensions/nested-loops.js b/src/extensions/nested-loops.js
index 1d0044b..19cba26 100644
--- a/src/extensions/nested-loops.js
+++ b/src/extensions/nested-loops.js
@@ -16,21 +16,87 @@ const deepThree = []
 // for (let i = 5; i < 7; i++) {
 // Your code here
 // }
+for(let i = 1; i <= 10; i++){
+  simpleOne.push(i)
+}
 
 // 2. Using nested for loops, add arrays to 'nestedOne' where each array has n copies of the outer 'loop index'
-//    eg [[1],[2,2],...]
+//    eg [[1],[2,2],...]'
+for(let i = 1; i <= 10; i++){
+  let lst = []
+  for(let j = 0; j < i; j++){
+    lst.push(i)
+  }
+  nestedOne.push(lst)
+}
+
 
 // 3. As 2, but each array should contain the values from the outer 'loop index' to 1 inclusive. Update array 'nestedTwo'
 //    eg [[1],[2,1],...]
+for(let i = 1; i <= 10; i++){
+  let lst = []
+  for(let j = i; j > 0; j--){
+    lst.push(j)
+  }
+  nestedTwo.push(lst)
+}
+
+
 
 // 4. As 2, but each array should contain arrays from 1 to the outer 'loop index' with the value of the outer 'loop index'. Update array 'deepOne'
 //    eg [[[1]],[[2],[2,2]],...]
+for (let i = 1; i <= 10; i++) {
+  const outerArray = [];
+  
+  for (let j = 1; j <= i; j++) {
+    const innerArray = Array(j).fill(i);
+    outerArray.push(innerArray);
+  }
+
+  deepOne.push(outerArray);
+}
+
 
 // 5. As 4, update array 'deepTwo' so that the result is:
 //       [[[1]],[[1],[1,2]],...]
+for (let i = 1; i <= 10; i++) {
+  const outerArray = [];
+  
+  for (let j = 1; j <= i; j++) {
+    const innerArray = [];
+    
+    for (let k = 1; k <= j; k++) {
+      innerArray.push(k);
+    }
+    
+    outerArray.push(innerArray);
+  }
+
+  deepTwo.push(outerArray);
+}
+
 
 // 6. As 5, update the array 'deepThree', but the result should be the average of the sum of the squares of the numbers in each array
 //       [[1],[[1],[2.5]],...]
+for (let i = 1; i <= 10; i++) { 
+  const outerArray = [];
+  
+  for (let j = 1; j <= i; j++) {
+    const numbers = [];
+    
+    for (let k = 1; k <= j; k++) {
+      numbers.push(k);
+    }
+    
+    const sumOfSquares = numbers.reduce((sum, num) => sum + (num * num), 0);
+    
+    const average = sumOfSquares / numbers.length;
+    
+    outerArray.push([average]);
+  }
+
+  deepThree.push(outerArray);
+}
 
 module.exports = {
   START,
diff --git a/src/for-loop-and-arrays.js b/src/for-loop-and-arrays.js
index 6635155..fa7f5a8 100644
--- a/src/for-loop-and-arrays.js
+++ b/src/for-loop-and-arrays.js
@@ -6,17 +6,34 @@ let word = '' // eslint-disable-line prefer-const
 // TODO: Add code below this line to make the tests pass
 
 // 1. Use a for loop to set the sum variable to the sum of all the values in nums
+for (let i = 0; i < nums.length; i++) {
+  sum += nums[i]
+}
 
 // 2. Use a for loop to populate doubledNums with every value from nums array doubled (i.e [2, 6, 24, etc...])
 const doubledNums = []
+for (let i = 0; i < nums.length; i++) {
+  doubledNums.push(nums[i] * 2)
+}
 
 // 3. Use a for loop to set word variable equal to all the letters in the letters array combined as a single string
+for (let i = 0; i < letters.length; i++){
+  word = word.concat(letters[i])
+}
+
 
 // 4. Use a for loop to populate everySecondNum with every second number from the nums array
 const everySecondNum = []
+for (let i = 1; i < nums.length; i += 2){
+  everySecondNum.push(nums[i])
+}
 
 // 5. Use a for loop to populate numsReversed with the numbers from nums in reverse order
 const numsReversed = []
+for(let i = nums.length- 1; i >= 0; i--){
+  numsReversed.push(nums[i])
+}
+
 
 // do not change below this line
 module.exports = {
diff --git a/src/for-loop-basic.js b/src/for-loop-basic.js
index dc3775a..78e500d 100644
--- a/src/for-loop-basic.js
+++ b/src/for-loop-basic.js
@@ -4,12 +4,27 @@ const evenNums = []
 const countdown = []
 
 // TODO: 1. Write a for loop that adds the numbers 0 to 3 to the numsZeroToThree array
+for (let index = 0; index <= 3; index++) {
+  numsZeroToThree.push(index)
+  
+}
 
 // TODO: 2. Write a for loop that adds the numbers 5 to 10 to the numsFiveToTen array
+for(let i = 5; i <= 10; i++){
+  numsFiveToTen.push(i)
+}
+
 
 // TODO: 3. Write a for loop that adds all the even numbers between 0 and 6 (0, 2, 4, 6) to evenNums
+for(let i = 0; i <= 6; i += 2){
+  evenNums.push(i)
+}
 
 // TODO: 4. Write a for loop that adds the numbers 3 to 0 (in that order) to the countdown array
+for(let i = 3; i >= 0; i--){
+  countdown.push(i)
+}
+
 
 // do not change below this line
 module.exports = {