diff --git a/Sprint-3/1-key-errors/0.js b/Sprint-3/1-key-errors/0.js
index 653d6f5a0..0c0a8242d 100644
--- a/Sprint-3/1-key-errors/0.js
+++ b/Sprint-3/1-key-errors/0.js
@@ -1,13 +1,21 @@
 // Predict and explain first...
-//  =============> write your prediction here
+// I believe this will cause an error because str is declared twice
 
 // call the function capitalise with a string input
 // interpret the error message and figure out why an error is occurring
 
-function capitalise(str) {
+/* function capitalise(str) {
   let str = `${str[0].toUpperCase()}${str.slice(1)}`;
   return str;
 }
+*/
+
+// The error happens because str is declared twice, once as a parameter & again with let
+// If I give the new variable a different name, I hope it should work :)
+
+function capitalise(str) {
+  let capitalisedString = `${str[0].toUpperCase()}${str.slice(1)}`;
+  return capitalisedString;
+}
 
-// =============> write your explanation here
-// =============> write your new code here
+console.log(capitalise("frumentius"));
diff --git a/Sprint-3/1-key-errors/1.js b/Sprint-3/1-key-errors/1.js
index f2d56151f..af93577c1 100644
--- a/Sprint-3/1-key-errors/1.js
+++ b/Sprint-3/1-key-errors/1.js
@@ -1,10 +1,12 @@
 // Predict and explain first...
 
 // Why will an error occur when this program runs?
-// =============> write your prediction here
+// Because decimalNumber is declared twice, once as a parameter and again with const
 
 // Try playing computer with the example to work out what is going on
 
+/*
+
 function convertToPercentage(decimalNumber) {
   const decimalNumber = 0.5;
   const percentage = `${decimalNumber * 100}%`;
@@ -12,9 +14,19 @@ function convertToPercentage(decimalNumber) {
   return percentage;
 }
 
-console.log(decimalNumber);
+console.log(convertToPercentage(decimalNumber)); */
 
-// =============> write your explanation here
+// decimalNumber is already a parameter, so declaring it again with const causes an error
+// decimalNumber has already been declared as a parameter in the same function scope
+// console.log(decimalNumber) is wrong because decimalNumber is not defined outside the function,
+// so we need to call the function with a value
 
 // Finally, correct the code to fix the problem
-// =============> write your new code here
+
+function convertToPercentage(decimalNumber) {
+  const percentage = `${decimalNumber * 100}%`;
+
+  return percentage;
+}
+
+console.log(convertToPercentage(0.7));
diff --git a/Sprint-3/1-key-errors/2.js b/Sprint-3/1-key-errors/2.js
index aad57f7cf..c0330bf46 100644
--- a/Sprint-3/1-key-errors/2.js
+++ b/Sprint-3/1-key-errors/2.js
@@ -1,20 +1,30 @@
-
 // Predict and explain first BEFORE you run any code...
 
 // this function should square any number but instead we're going to get an error
 
 // =============> write your prediction of the error here
+// I think using 3 will cause an error as parameter
+// A parameter must be a valid variable name, not a number
+
+/* function square(3){
+   return  num * num;
 
-function square(3) {
-    return num * num;
 }
+   */
 
 // =============> write the error message here
+// SyntaxError: Unexpected number
 
 // =============> explain this error message here
+// The parser sees the number 3 where it expects a valid parameter name,
+// so it cannot understand the structure of the function
+// It means we cannot use a number as a parameter name
 
 // Finally, correct the code to fix the problem
 
 // =============> write your new code here
 
-
+function square(num) {
+  return num * num;
+}
+console.log(square(7));
diff --git a/Sprint-3/2-mandatory-debug/0.js b/Sprint-3/2-mandatory-debug/0.js
index b27511b41..e2679cf2e 100644
--- a/Sprint-3/2-mandatory-debug/0.js
+++ b/Sprint-3/2-mandatory-debug/0.js
@@ -1,14 +1,24 @@
 // Predict and explain first...
 
 // =============> write your prediction here
+// I believe the function will calculate 10 x 32
 
-function multiply(a, b) {
+/* function multiply(a, b) {
   console.log(a * b);
 }
 
-console.log(`The result of multiplying 10 and 32 is ${multiply(10, 32)}`);
+console.log(`The result of multiplying 10 and 32 is ${multiply(10, 32)}`); */
 
 // =============> write your explanation here
 
+// After calling multiply(10, 32), the result is undefined because there is no return statement
+// It can still print 320 because console.log() prints the result inside the function
+
 // Finally, correct the code to fix the problem
 //  =============> write your new code here
+
+function multiply(a, b) {
+  
+  return a * b;
+}
+console.log(`The result of multiplying 10 and 32 is ${multiply(10, 32)}`);
diff --git a/Sprint-3/2-mandatory-debug/1.js b/Sprint-3/2-mandatory-debug/1.js
index 37cedfbcf..45d4b156f 100644
--- a/Sprint-3/2-mandatory-debug/1.js
+++ b/Sprint-3/2-mandatory-debug/1.js
@@ -1,13 +1,22 @@
 // Predict and explain first...
 //  =============> write your prediction here
+// I guess the function will return error or undefined because the return;
 
-function sum(a, b) {
+/*function sum(a, b) {
   return;
   a + b;
 }
 
-console.log(`The sum of 10 and 32 is ${sum(10, 32)}`);
+console.log(`The sum of 10 and 32 is ${sum(10, 32)}`); */
 
 // =============> write your explanation here
+// The problem is the semicolon immediately after return that prevent to reach out to a + b
+
 // Finally, correct the code to fix the problem
 //  =============> write your new code here
+
+function sum(a, b) {
+  return a + b;
+}
+
+console.log(`The sum of 10 and 32 is ${sum(10, 32)}`);
diff --git a/Sprint-3/2-mandatory-debug/2.js b/Sprint-3/2-mandatory-debug/2.js
index 57d3f5dc3..b10031f3a 100644
--- a/Sprint-3/2-mandatory-debug/2.js
+++ b/Sprint-3/2-mandatory-debug/2.js
@@ -2,8 +2,9 @@
 
 // Predict the output of the following code:
 // =============> Write your prediction here
+// The output will be the same because we don't give the function a parameter
 
-const num = 103;
+/*const num = 103;
 
 function getLastDigit() {
   return num.toString().slice(-1);
@@ -11,14 +12,30 @@ function getLastDigit() {
 
 console.log(`The last digit of 42 is ${getLastDigit(42)}`);
 console.log(`The last digit of 105 is ${getLastDigit(105)}`);
-console.log(`The last digit of 806 is ${getLastDigit(806)}`);
+console.log(`The last digit of 806 is ${getLastDigit(806)}`); */
 
 // Now run the code and compare the output to your prediction
 // =============> write the output here
+// The output is the same but the last digit is 3
+
 // Explain why the output is the way it is
 // =============> write your explanation here
+// Because of the global variable and also because the function has no parameter
+
 // Finally, correct the code to fix the problem
 // =============> write your new code here
 
+
+
+function getLastDigit(num) {
+  return num.toString().slice(-1);
+}
+
+console.log(`The last digit of 42 is ${getLastDigit(42)}`);
+console.log(`The last digit of 105 is ${getLastDigit(105)}`);
+console.log(`The last digit of 806 is ${getLastDigit(806)}`);
+
 // This program should tell the user the last digit of each number.
 // Explain why getLastDigit is not working properly - correct the problem
+
+// Because the function was using the global variable, it ignored the arguments passed to it outside of the function box
diff --git a/Sprint-3/3-mandatory-implement/1-bmi.js b/Sprint-3/3-mandatory-implement/1-bmi.js
index 58b1085f1..3bde88c40 100644
--- a/Sprint-3/3-mandatory-implement/1-bmi.js
+++ b/Sprint-3/3-mandatory-implement/1-bmi.js
@@ -15,5 +15,10 @@
 // It should return a string of their Body Mass Index to 1 decimal place
 
 function calculateBMI(weight, height) {
-  // return the BMI of someone based off their weight and height
+  let BMI = weight / (height * height);
+
+  return BMI.toFixed(1);
 }
+console.log(calculateBMI(62, 1.67));
+
+// return the BMI of someone based off their weight and height
diff --git a/Sprint-3/3-mandatory-implement/2-cases.js b/Sprint-3/3-mandatory-implement/2-cases.js
index 5b0ef77ad..605ce8295 100644
--- a/Sprint-3/3-mandatory-implement/2-cases.js
+++ b/Sprint-3/3-mandatory-implement/2-cases.js
@@ -14,3 +14,9 @@
 // You will need to come up with an appropriate name for the function
 // Use the MDN string documentation to help you find a solution
 // This might help https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/toUpperCase
+
+function toUpperSnakeCase(input) {
+  return input.replaceAll(" ", "_").toUpperCase();
+}
+
+console.log(toUpperSnakeCase("alpha and omega"));
diff --git a/Sprint-3/3-mandatory-implement/3-to-pounds.js b/Sprint-3/3-mandatory-implement/3-to-pounds.js
index 10754da73..ee41cc557 100644
--- a/Sprint-3/3-mandatory-implement/3-to-pounds.js
+++ b/Sprint-3/3-mandatory-implement/3-to-pounds.js
@@ -4,3 +4,21 @@
 // You will need to declare a function called toPounds with an appropriately named parameter.
 
 // You should call this function a number of times to check it works for different inputs
+
+function toPounds(amount) {
+  const amountWithoutTrailingP = amount.substring(0, amount.length - 1);
+
+  const paddedPenceNumberString = amountWithoutTrailingP.padStart(3, "0");
+  const pounds = paddedPenceNumberString.substring(
+    0,
+    paddedPenceNumberString.length - 2,
+  );
+
+  const pence = paddedPenceNumberString
+    .substring(paddedPenceNumberString.length - 2)
+    .padEnd(2, "0");
+
+  return `£${pounds}.${pence}`;
+}
+
+console.log(toPounds("1250p"));
diff --git a/Sprint-3/4-mandatory-interpret/time-format.js b/Sprint-3/4-mandatory-interpret/time-format.js
index c0dd9c9a5..a99388fa0 100644
--- a/Sprint-3/4-mandatory-interpret/time-format.js
+++ b/Sprint-3/4-mandatory-interpret/time-format.js
@@ -14,6 +14,7 @@ function formatTimeDisplay(seconds) {
 
   return `${pad(totalHours)}:${pad(remainingMinutes)}:${pad(remainingSeconds)}`;
 }
+console.log(formatTimeDisplay(61));
 
 // You will need to play computer with this example - use the Python Visualiser https://pythontutor.com/visualize.html#mode=edit
 // to help you answer these questions
@@ -21,18 +22,18 @@ function formatTimeDisplay(seconds) {
 // Questions
 
 // a) When formatTimeDisplay is called how many times will pad be called?
-// =============> write your answer here
+// 3
 
 // Call formatTimeDisplay with an input of 61, now answer the following:
 
 // b) What is the value assigned to num when pad is called for the first time?
-// =============> write your answer here
+// 0
 
 // c) What is the return value of pad when it is called for the first time?
-// =============> write your answer here
+// "00"
 
 // d) What is the value assigned to num when pad is called for the last time in this program?  Explain your answer
-// =============> write your answer here
+// 1
 
 // e) What is the return value of pad when it is called for the last time in this program?  Explain your answer
-// =============> write your answer here
+// "01"
diff --git a/Sprint-3/5-stretch-extend/format-time.js b/Sprint-3/5-stretch-extend/format-time.js
index 32a32e66b..f86d01511 100644
--- a/Sprint-3/5-stretch-extend/format-time.js
+++ b/Sprint-3/5-stretch-extend/format-time.js
@@ -14,12 +14,12 @@ const currentOutput = formatAs12HourClock("08:00");
 const targetOutput = "08:00 am";
 console.assert(
   currentOutput === targetOutput,
-  `current output: ${currentOutput}, target output: ${targetOutput}`
+  `current output: ${currentOutput}, target output: ${targetOutput}`,
 );
 
 const currentOutput2 = formatAs12HourClock("23:00");
 const targetOutput2 = "11:00 pm";
 console.assert(
   currentOutput2 === targetOutput2,
-  `current output: ${currentOutput2}, target output: ${targetOutput2}`
+  `current output: ${currentOutput2}, target output: ${targetOutput2}`,
 );