diff --git a/README.md b/README.md
index 5833a402f..2e6079265 100644
--- a/README.md
+++ b/README.md
@@ -2,7 +2,7 @@
 
 Like learning a musical instrument, programming requires daily practise.
 
-The exercises are split into three folders: `exercises`, `mandatory` and `extra`. All homework in the `exercise` and `mandatory` section **must** be completed for homework by the following lesson. 
+The exercises are split into three folders: `exercises`, `mandatory` and `extra`. All homework in the `exercise` and `mandatory` section **must** be completed for homework by the following lesson.
 
 The `extra` folder contains exercises that you can complete to challenge yourself, but are not required for the following lesson.
 
diff --git a/exercises/D-strings/exercise.js b/exercises/D-strings/exercise.js
index 2cffa6a81..227aeb005 100644
--- a/exercises/D-strings/exercise.js
+++ b/exercises/D-strings/exercise.js
@@ -1,3 +1,6 @@
 // Start by creating a variable `message`
+var message = "This is a string";
+var messageType = typeof message;
 
 console.log(message);
+console.log(messageType); // logs 'string'
diff --git a/exercises/E-strings-concatenation/exercise.js b/exercises/E-strings-concatenation/exercise.js
index 2cffa6a81..d6e551de2 100644
--- a/exercises/E-strings-concatenation/exercise.js
+++ b/exercises/E-strings-concatenation/exercise.js
@@ -1,3 +1,5 @@
 // Start by creating a variable `message`
 
-console.log(message);
+const message = "Hello, my name is ";
+const name = "Georgina";
+console.log(message + name);
diff --git a/exercises/F-strings-methods/exercise.js b/exercises/F-strings-methods/exercise.js
index 2cffa6a81..58e14bd84 100644
--- a/exercises/F-strings-methods/exercise.js
+++ b/exercises/F-strings-methods/exercise.js
@@ -1,3 +1,16 @@
 // Start by creating a variable `message`
+//  const myName = "Georgina";
+// var nameLength = Georgina.length;
+
+// console.log(nameLength); // Logs 8
+
+
+
+ const myName = "Georgina ";
+ console.log(
+   `My name is ${myName}, the length of my name is ${myName.length} characters`
+ ); 
+console.log();
+
+
 
-console.log(message);
diff --git a/exercises/F-strings-methods/exercise2.js b/exercises/F-strings-methods/exercise2.js
index b4b46943d..931a25694 100644
--- a/exercises/F-strings-methods/exercise2.js
+++ b/exercises/F-strings-methods/exercise2.js
@@ -1,3 +1,13 @@
-const name = " Daniel  ";
+// const name = " Georgina  ";
 
-console.log(message);
+// console.log(
+//   `My name is ${Name}, the length of my name is ${Name.length} characters`
+// );
+
+// console.log(message);
+const name = " Georgina  ";
+console.log(
+  `My name is ${name.trim()}, the length of my name is ${
+    name.trim().length
+  } characters`
+);
diff --git a/exercises/G-numbers/exercise.js b/exercises/G-numbers/exercise.js
index 49e7bc00b..5571fa962 100644
--- a/exercises/G-numbers/exercise.js
+++ b/exercises/G-numbers/exercise.js
@@ -1 +1,7 @@
 // Start by creating a variables `numberOfStudents` and `numberOfMentors`
+const numberOfStudents = "15";
+const numberOfMentors = "8";
+
+const sum = 15 + 8; // 23
+
+console.log(sum);
diff --git a/exercises/I-floats/exercise.js b/exercises/I-floats/exercise.js
index a5bbcd852..e293065cd 100644
--- a/exercises/I-floats/exercise.js
+++ b/exercises/I-floats/exercise.js
@@ -1,2 +1,21 @@
-var numberOfStudents = 15;
-var numberOfMentors = 8;
+const numberOfStudents = 15;
+const numberOfMentors = 8;
+const sum = numberOfStudents + numberOfMentors;
+
+// console.log (TotalnumberOfStudents ${numberOfStudents} );
+
+// console.log (TotalnumberOfMentors ${numberOfMentors } );
+
+//console.log (TotalNumber ${totalNumber} );
+
+const percentageStudents = (numberOfStudents/sum) * 100;//65
+
+console.log (percentageStudents)
+
+const percentageMentors = (numberOfMentors/sum) * 100;//34.7 (math.round =35
+
+console.log (percentageMentors)
+
+
+
+
diff --git a/exercises/J-functions/exercise.js b/exercises/J-functions/exercise.js
index 0ae5850e5..c98e4737f 100644
--- a/exercises/J-functions/exercise.js
+++ b/exercises/J-functions/exercise.js
@@ -1,7 +1,16 @@
 function halve(number) {
   // complete the function here
+
+  return number /2;
 }
 
 var result = halve(12);
 
-console.log(result);
+console.log(result);//6
+
+var result = halve(10);
+console.log (result); //5
+
+var result = halve(100);
+console.log (result); //50
+
diff --git a/exercises/J-functions/exercise2.js b/exercises/J-functions/exercise2.js
index 82ef5e780..36d52ef48 100644
--- a/exercises/J-functions/exercise2.js
+++ b/exercises/J-functions/exercise2.js
@@ -1,7 +1,8 @@
 function triple(number) {
   // complete function here
+  return number * 3;
 }
 
 var result = triple(12);
 
-console.log(result);
+console.log(result); //36
diff --git a/exercises/K-functions-parameters/exercise.js b/exercises/K-functions-parameters/exercise.js
index 8d5db5e69..36cf19f47 100644
--- a/exercises/K-functions-parameters/exercise.js
+++ b/exercises/K-functions-parameters/exercise.js
@@ -1,9 +1,11 @@
 // Complete the function so that it takes input parameters
-function multiply() {
+function multiply (numberOne, numberTwo) {
+ 
   // Calculate the result of the function and return it
+   return numberOne * numberTwo;
 }
 
 // Assign the result of calling the function the variable `result`
-var result = multiply(3, 4);
+var result = multiply(3, 4);//12
 
 console.log(result);
diff --git a/exercises/K-functions-parameters/exercise2.js b/exercises/K-functions-parameters/exercise2.js
index db7a8904b..e11abbcc8 100644
--- a/exercises/K-functions-parameters/exercise2.js
+++ b/exercises/K-functions-parameters/exercise2.js
@@ -1,5 +1,6 @@
 // Declare your function first
-
+function divide(numberOne, numberTwo) {
+  return numberOne / numberTwo;
+}
 var result = divide(3, 4);
-
 console.log(result);
diff --git a/exercises/K-functions-parameters/exercise3.js b/exercises/K-functions-parameters/exercise3.js
index 537e9f4ec..11ac63998 100644
--- a/exercises/K-functions-parameters/exercise3.js
+++ b/exercises/K-functions-parameters/exercise3.js
@@ -1,5 +1,9 @@
 // Write your function here
+function greeting(greetingStart, name) {}
+//var greeting = createGreeting("Daniel");
+var greetingStart = "Hello, my name is ";
+var name = "Georgina";
 
-var greeting = createGreeting("Daniel");
+greeting = greetingStart + name;
 
-console.log(greeting);
+console.log(greeting); // Logs "Hello, my name is Georgina"
diff --git a/exercises/K-functions-parameters/exercise4.js b/exercises/K-functions-parameters/exercise4.js
index 7ab44589e..1897c5cff 100644
--- a/exercises/K-functions-parameters/exercise4.js
+++ b/exercises/K-functions-parameters/exercise4.js
@@ -1,5 +1,8 @@
 // Declare your function first
-
+function addition(numberOne, numberTwo) {
+  return numberOne + numberTwo;
+}
 // Call the function and assign to a variable `sum`
 
+const sum = addition(13, 124);
 console.log(sum);
diff --git a/exercises/K-functions-parameters/exercise5.js b/exercises/K-functions-parameters/exercise5.js
index 7c5bcd605..1d57b4da5 100644
--- a/exercises/K-functions-parameters/exercise5.js
+++ b/exercises/K-functions-parameters/exercise5.js
@@ -1,5 +1,10 @@
 // Declare your function here
+//function greeting(greetingStart, name, age) {
+function createLongGreeting(name, age) {
+  return `Hello, my name is ${name} and I'm ${age} years old`;
+}
 
-const greeting = createLongGreeting("Daniel", 30);
+//var greeting = createGreeting("Georgina");
+const greeting = createLongGreeting("Georgina", 43);
 
 console.log(greeting);
diff --git a/exercises/L-functions-nested/exercise.js b/exercises/L-functions-nested/exercise.js
index a5d377442..33763325c 100644
--- a/exercises/L-functions-nested/exercise.js
+++ b/exercises/L-functions-nested/exercise.js
@@ -3,3 +3,23 @@ var mentor2 = "Irina";
 var mentor3 = "Mimi";
 var mentor4 = "Rob";
 var mentor5 = "Yohannes";
+
+var mentor3 = "Mimi";
+var mentor4 = "Rob";
+var mentor5 = "Yohannes";
+
+function CreateGreeting(name) {
+  return `HELLO ${name}`;
+}
+
+function ToUpper(string) {
+  return CreateGreeting(string.toUpperCase());
+}
+
+console.log(ToUpper(mentor1));
+console.log(ToUpper(mentor2));
+console.log(ToUpper(mentor3));
+console.log(ToUpper(mentor4));
+console.log(ToUpper(mentor5));
+
+console.log("\n");
diff --git a/mandatory/1-syntax-errors.js b/mandatory/1-syntax-errors.js
index a10cc9ac2..ef331ca2a 100644
--- a/mandatory/1-syntax-errors.js
+++ b/mandatory/1-syntax-errors.js
@@ -1,18 +1,24 @@
 // There are syntax errors in this code - can you fix it to pass the tests?
 
-function addNumbers(a b c) {
+function addNumbers(a, b, c) {
   return a + b + c;
 }
+addNumbers(3, 4, 6);
+
+function introduceMe(name, age) {
+  return "Hello, my name is " + name  + " and I am " + age + "years old";
+}
+introduceMe("Sonjid", 27);
 
-function introduceMe(name, age)
-  return "Hello, my name is " + name "and I am " age + "years old";
 
 function getTotal(a, b) {
-  total = a ++ b;
+  total = a + b;
 
-  return "The total is total";
+  return "The total is " + total;
 }
 
+getTotal(23, 5);
+
 /* 
 ===================================================
 ======= TESTS - DO NOT MODIFY BELOW THIS LINE =====
diff --git a/mandatory/2-logic-error.js b/mandatory/2-logic-error.js
index 9cca7603b..37c4ebc15 100644
--- a/mandatory/2-logic-error.js
+++ b/mandatory/2-logic-error.js
@@ -1,16 +1,15 @@
 // The syntax for this function is valid but it has an error, find it and fix it.
 
 function trimWord(word) {
-  return wordtrim();
+  return word.trim();
 }
 
 function getStringLength(word) {
-  return "word".length();
+  return word.length;
 }
 
 function multiply(a, b, c) {
-  a * b * c;
-  return;
+  return a * b * c;
 }
 
 /* 
diff --git a/mandatory/3-function-output.js b/mandatory/3-function-output.js
index 5a953ba60..36ff46a8f 100644
--- a/mandatory/3-function-output.js
+++ b/mandatory/3-function-output.js
@@ -1,16 +1,35 @@
 // Add comments to explain what this function does. You're meant to use Google!
+//This function generates a random decimal value between 0 and 1
 function getRandomNumber() {
-  return Math.random() * 10;
+  return Math.random() * 10; //The Math.random() function returns a floating-point, pseudo-random number in the range 0 to less than 1 (inclusive of 0, but not 1) with approximately uniform distribution over that range
 }
 
 // Add comments to explain what this function does. You're meant to use Google!
 function combine2Words(word1, word2) {
   return word1.concat(word2);
+  return word1.concat(word2); //to join two or more text strings into one string
 }
 
 function concatenate(firstWord, secondWord, thirdWord) {
   // Write the body of this function to concatenate three words together.
   // Look at the test case below to understand what this function is expected to return.
+  return firstWord.concat(" ", secondWord, " ", thirdWord);
+}
+
+/* 
+
+}
+
+// Add comments to explain what this function does. You're meant to use Google!
+//This function is used to join two strings
+function combine2Words(word1, word2) {
+  return word1.concat(word2);
+}
+
+function concatenate(firstWord, secondWord, thirdWord) {
+   return firstWord.concat(" ", secondWord, " ", thirdWord);
+  // Write the body of this function to concatenate three words together.
+  // Look at the test case below to understand what this function is expected to return.
 }
 
 /* 
diff --git a/mandatory/4-tax.js b/mandatory/4-tax.js
index ba77c7ae2..6748243dd 100644
--- a/mandatory/4-tax.js
+++ b/mandatory/4-tax.js
@@ -18,6 +18,15 @@ function calculateSalesTax() {}
 */
 
 function addTaxAndFormatCurrency() {}
+function calculateSalesTax(beforeSalesTax) {
+  // return the total price then multiply by tax percentage
+  return beforeSalesTax + beforeSalesTax * 0.2;
+}
+
+function addTaxAndFormatCurrency(numberToFormat) {
+  // returns: total price + tax using £ as the start currency symbol. Price has 2 decimal places at the end via .toFixed()
+  return `£${(numberToFormat + numberToFormat * 0.2).toFixed(2)}`;
+}
 
 /* 
 ===================================================