diff --git a/Sprint-1/1-key-exercises/1-count.js b/Sprint-1/1-key-exercises/1-count.js
index 117bcb2b6..289729754 100644
--- a/Sprint-1/1-key-exercises/1-count.js
+++ b/Sprint-1/1-key-exercises/1-count.js
@@ -4,3 +4,7 @@ count = count + 1;
 
 // Line 1 is a variable declaration, creating the count variable with an initial value of 0
 // Describe what line 3 is doing, in particular focus on what = is doing
+
+// SOLUTION:
+// Line 3 is updating the value of the count by adding 1 to its value.
+// line 3 uses the assignment operator which is = and while count increases by one, increment stores additional 1 to the count variable.
\ No newline at end of file
diff --git a/Sprint-1/1-key-exercises/2-initials.js b/Sprint-1/1-key-exercises/2-initials.js
index 47561f617..92aa6a726 100644
--- a/Sprint-1/1-key-exercises/2-initials.js
+++ b/Sprint-1/1-key-exercises/2-initials.js
@@ -5,7 +5,9 @@ let lastName = "Johnson";
 // Declare a variable called initials that stores the first character of each string.
 // This should produce the string "CKJ", but you must not write the characters C, K, or J in the code of your solution.
 
-let initials = ``;
+let initials = firstName[0] + middleName[0] + lastName[0];
+
+console.log(initials);
 
 // https://www.google.com/search?q=get+first+character+of+string+mdn
 
diff --git a/Sprint-1/1-key-exercises/3-paths.js b/Sprint-1/1-key-exercises/3-paths.js
index ab90ebb28..3cec456e0 100644
--- a/Sprint-1/1-key-exercises/3-paths.js
+++ b/Sprint-1/1-key-exercises/3-paths.js
@@ -17,7 +17,7 @@ console.log(`The base part of ${filePath} is ${base}`);
 // Create a variable to store the dir part of the filePath variable
 // Create a variable to store the ext part of the variable
 
-const dir = ;
-const ext = ;
+const dir = filePath.slice(0, lastSlashIndex);
+const ext = filePath.slice(lastSlashIndex + 1);
 
 // https://www.google.com/search?q=slice+mdn
\ No newline at end of file
diff --git a/Sprint-1/1-key-exercises/4-random.js b/Sprint-1/1-key-exercises/4-random.js
index 292f83aab..9fac0fbc3 100644
--- a/Sprint-1/1-key-exercises/4-random.js
+++ b/Sprint-1/1-key-exercises/4-random.js
@@ -1,5 +1,6 @@
 const minimum = 1;
 const maximum = 100;
+const num = 2;
 
 const num = Math.floor(Math.random() * (maximum - minimum + 1)) + minimum;
 
@@ -7,3 +8,13 @@ const num = Math.floor(Math.random() * (maximum - minimum + 1)) + minimum;
 // Try breaking down the expression and using documentation to explain what it means
 // It will help to think about the order in which expressions are evaluated
 // Try logging the value of num and running the program several times to build an idea of what the program is doing
+
+
+
+// SOLUTION:
+
+// In this program, variable num is assigned to a value between 1 and 100.
+
+// In 5th line, expressions of math.floor and math.random are used to generate a random number between the minimum and maximum numbers that are defined by first const minimum= 1 and second const maximum = 100.
+
+// Also math.floor is used to round down the random number generated by math random to get to the nearest whole number.
\ No newline at end of file
diff --git a/Sprint-1/2-mandatory-errors/0.js b/Sprint-1/2-mandatory-errors/0.js
index cf6c5039f..098f0b365 100644
--- a/Sprint-1/2-mandatory-errors/0.js
+++ b/Sprint-1/2-mandatory-errors/0.js
@@ -1,2 +1,4 @@
 This is just an instruction for the first activity - but it is just for human consumption
-We don't want the computer to run these 2 lines - how can we solve this problem?
\ No newline at end of file
+We don't want the computer to run these 2 lines - how can we solve this problem?
+
+// We can use a comment to prevent the computer from running these lines.
\ No newline at end of file
diff --git a/Sprint-1/2-mandatory-errors/1.js b/Sprint-1/2-mandatory-errors/1.js
index 7a43cbea7..aed29ff4e 100644
--- a/Sprint-1/2-mandatory-errors/1.js
+++ b/Sprint-1/2-mandatory-errors/1.js
@@ -1,4 +1,8 @@
 // trying to create an age variable and then reassign the value by 1
 
-const age = 33;
+let age = 33;
 age = age + 1;
+
+console.log(age);
+
+
diff --git a/Sprint-1/2-mandatory-errors/2.js b/Sprint-1/2-mandatory-errors/2.js
index e09b89831..08e662ab6 100644
--- a/Sprint-1/2-mandatory-errors/2.js
+++ b/Sprint-1/2-mandatory-errors/2.js
@@ -1,5 +1,6 @@
 // Currently trying to print the string "I was born in Bolton" but it isn't working...
 // what's the error ?
-
-console.log(`I was born in ${cityOfBirth}`);
 const cityOfBirth = "Bolton";
+console.log(`I was born in ${cityOfBirth}`);
+
+//Code was correct, I just shifted the const part to the top of the code block.
\ No newline at end of file
diff --git a/Sprint-1/2-mandatory-errors/3.js b/Sprint-1/2-mandatory-errors/3.js
index ec101884d..507f13bb1 100644
--- a/Sprint-1/2-mandatory-errors/3.js
+++ b/Sprint-1/2-mandatory-errors/3.js
@@ -1,5 +1,8 @@
 const cardNumber = 4533787178994213;
-const last4Digits = cardNumber.slice(-4);
+const last4Digits = cardNumber.toString().slice(-4);
+
+
+console.log(last4Digits);
 
 // The last4Digits variable should store the last 4 digits of cardNumber
 // However, the code isn't working
@@ -7,3 +10,12 @@ const last4Digits = cardNumber.slice(-4);
 // Then run the code and see what error it gives.
 // Consider: Why does it give this error? Is this what I predicted? If not, what's different?
 // Then try updating the expression last4Digits is assigned to, in order to get the correct value
+
+
+// Prediction; code wont work because slice is for strings, not numbers.
+
+// after running the code, I got an error saying "cardNumber.slice is not a function".
+
+// It's what I predicted.
+
+// to fix the code I need to convert number to string first, then slice it.
diff --git a/Sprint-1/2-mandatory-errors/4.js b/Sprint-1/2-mandatory-errors/4.js
index 21dad8c5d..7c9aae422 100644
--- a/Sprint-1/2-mandatory-errors/4.js
+++ b/Sprint-1/2-mandatory-errors/4.js
@@ -1,2 +1,12 @@
-const 12HourClockTime = "20:53";
-const 24hourClockTime = "08:53";
\ No newline at end of file
+//const 12HourClockTime = "20:53";
+//const 24hourClockTime = "08:53";
+
+
+// problem is in javascript we cant start a variable name with a number.
+
+// correct way is:
+
+const twelveHourClockTime = "20:53";
+const twentyFourHourClockTime = "08:53";
+
+console.log(`The time in 12-hour format is ${twelveHourClockTime} and in 24-hour format is ${twentyFourHourClockTime}`);
diff --git a/Sprint-1/3-mandatory-interpret/1-percentage-change.js b/Sprint-1/3-mandatory-interpret/1-percentage-change.js
index e24ecb8e1..f959d4acf 100644
--- a/Sprint-1/3-mandatory-interpret/1-percentage-change.js
+++ b/Sprint-1/3-mandatory-interpret/1-percentage-change.js
@@ -2,7 +2,7 @@ let carPrice = "10,000";
 let priceAfterOneYear = "8,543";
 
 carPrice = Number(carPrice.replaceAll(",", ""));
-priceAfterOneYear = Number(priceAfterOneYear.replaceAll("," ""));
+priceAfterOneYear = Number(priceAfterOneYear.replaceAll(",", ""));
 
 const priceDifference = carPrice - priceAfterOneYear;
 const percentageChange = (priceDifference / carPrice) * 100;
@@ -20,3 +20,18 @@ console.log(`The percentage change is ${percentageChange}`);
 // d) Identify all the lines that are variable declarations
 
 // e) Describe what the expression Number(carPrice.replaceAll(",","")) is doing - what is the purpose of this expression?
+
+
+// a) There are 5 function calls in this file:
+//  `carPrice.replaceAll(",", "")` on line 5
+//  `priceAfterOneYear.replaceAll(",", "")` on line 6
+//  `Number(...)` on lines 4 and 5
+// console.log on line 10.
+// b) A comma is missing between the first and second string arguments which causes the error.
+//c) The variable reassignment statements are:
+//  `carPrice = Number(carPrice.replaceAll(",", ""));` on line 5
+//  `priceAfterOneYear = Number(priceAfterOneYear.replaceAll(",", ""));` on line 6
+// d) The variable declarations are:
+// `let carPrice = "10,000";` on line 1
+// `let priceAfterOneYear = "8,543";` on line 2
+// e) The expression `Number(carPrice.replaceAll(",", ""))` is converting car price, which contains a comma, into a number.  
\ No newline at end of file
diff --git a/Sprint-1/3-mandatory-interpret/2-time-format.js b/Sprint-1/3-mandatory-interpret/2-time-format.js
index 47d239558..72db347ca 100644
--- a/Sprint-1/3-mandatory-interpret/2-time-format.js
+++ b/Sprint-1/3-mandatory-interpret/2-time-format.js
@@ -23,3 +23,30 @@ console.log(result);
 // e) What do you think the variable result represents? Can you think of a better name for this variable?
 
 // f) Try experimenting with different values of movieLength. Will this code work for all values of movieLength? Explain your answer
+
+
+// a) There are 6 variable declarations in this program:
+// which are:
+
+// movieLength
+
+// remainingSeconds
+
+// totalMinutes
+
+// remainingMinutes
+
+// totalHours
+
+// result
+
+// b) There are 2 function calls in this program.
+
+// c) Expression movieLength %60 represents remainder of division by 60.
+
+// d) expression assigned to totalminutes means minutes in the movie by removing the remaining seconds and dividing by 60.
+
+// e) Result variable represents the total time. A better name would be totalTime.
+
+// f) Yes code will work for all the values of movielength. It'll always return the total time with no problems. But It's not working if movielength less than 60 seconds, more than 24 hours or negative values.
+
diff --git a/Sprint-1/3-mandatory-interpret/3-to-pounds.js b/Sprint-1/3-mandatory-interpret/3-to-pounds.js
index 60c9ace69..99c649ec9 100644
--- a/Sprint-1/3-mandatory-interpret/3-to-pounds.js
+++ b/Sprint-1/3-mandatory-interpret/3-to-pounds.js
@@ -12,8 +12,7 @@ const pounds = paddedPenceNumberString.substring(
 );
 
 const pence = paddedPenceNumberString
-  .substring(paddedPenceNumberString.length - 2)
-  .padEnd(2, "0");
+  .substring(paddedPenceNumberString.length - 2);
 
 console.log(`£${pounds}.${pence}`);
 
@@ -25,3 +24,13 @@ console.log(`£${pounds}.${pence}`);
 
 // To begin, we can start with
 // 1. const penceString = "399p": initialises a string variable with the value "399p"
+
+// 2. const penceStringWithoutTrailingP = penceString.substring(0, penceString.length - 1): This line removes the trailing 'p' from the string.
+
+// 3. const paddedPenceNumberString = penceStringWithoutTrailingP.padStart(3, "0"): This line puts the string into a 3 character string padding with zeros.
+
+// 4. const pounds = paddedPenceNumberString.substring(0, paddedPenceNumberString.length - 2): This line takes out the pounds part of the string.
+
+// 5. const pence = paddedPenceNumberString.substring(paddedPenceNumberString.length - 2).padEnd(2, "0"): This line takes out pence part and pads it to 2 characters.
+
+// 6. console.log(`£${pounds}.${pence}`): This line prints the final results.
\ No newline at end of file