diff --git a/src/challenge.ts b/src/challenge.ts
index 63a7766..a1514ff 100644
--- a/src/challenge.ts
+++ b/src/challenge.ts
@@ -9,6 +9,7 @@
 // logger<number | string>([1, 2, 3, "one", "two", "three"]);
 function logger<T>(array: T[]): void {
   // write your code here...
+  array.forEach(element => console.log(element));
 }
 
 // `toCelsius` function that:
@@ -19,8 +20,7 @@ function logger<T>(array: T[]): void {
 // toCelsius([32, 68, 100, 212]); // => [0, 20, 37.7778, 100]
 function toCelsius(temperatures: number[]): number[] {
   // write your code here...
-
-  return []; // replace empty array with what you see is fit
+  return temperatures.map(number => (number-32) * (5/9))
 }
 
 // `hottestDays` function that:
@@ -32,8 +32,7 @@ function toCelsius(temperatures: number[]): number[] {
 // hottestDays([80, 90, 100, 110], 95); // => [100, 110]
 function hottestDays(temperatures: number[], threshold: number): number[] {
   // write your code here...
-
-  return []; // replace empty array with what you see is fit
+  return temperatures.filter(temperature => temperature > threshold)
 }
 
 // `logHottestDays` function that:
@@ -42,6 +41,7 @@ function hottestDays(temperatures: number[], threshold: number): number[] {
 // - Log temperatures that exceed the threshold to the console IN DEGREES CELSIUS  (hint: you can combine all previous functions)
 function logHottestDays(temperatures: number[], threshold: number): void {
   // write your code here...
+  logger(toCelsius(hottestDays(temperatures, threshold)))
 }
 
 export { logger, toCelsius, hottestDays, logHottestDays };
diff --git a/src/filtering.ts b/src/filtering.ts
index 49411d8..381c800 100644
--- a/src/filtering.ts
+++ b/src/filtering.ts
@@ -11,8 +11,7 @@ const numbers = [10, 13, 20, 25, 38, 35, 40];
 // greaterThanTwentyFive(numbers); // => [38, 35, 40]
 function greaterThanTwentyFive(numbers: number[]): number[] {
   // write your code here...
-
-  return []; // replace empty array with what you see is fit
+  return numbers.filter(number => number >= 25)
 }
 
 // `divisibleByFive` function that:
@@ -22,8 +21,7 @@ function greaterThanTwentyFive(numbers: number[]): number[] {
 // divisibleByFive(numbers); // => [10, 20, 25, 35, 40]
 function divisibleByFive(numbers: number[]): number[] {
   // write your code here...
-
-  return []; // replace empty array with what you see is fit
+  return numbers.filter(number => number % 5 == 0)
 }
 
 export { greaterThanTwentyFive, divisibleByFive };
diff --git a/src/mapping+filtering.ts b/src/mapping+filtering.ts
index 269ad83..5c1f05b 100644
--- a/src/mapping+filtering.ts
+++ b/src/mapping+filtering.ts
@@ -11,8 +11,7 @@ const numbers = [10, 13, 20, 25, 38, 35, 40];
 // filteredAndSquared(numbers); // => [400, 625, 1444, 1225, 1600]
 function filteredAndSquared(numbers: number[]): number[] {
   // write your code here...
-
-  return []; // replace empty array with what you see is fit
+  return numbers.filter(number => number >= 20).map(number => number ** 2)
 }
 
 // `filteredAndTripled` function that:
@@ -22,8 +21,7 @@ function filteredAndSquared(numbers: number[]): number[] {
 // filteredAndTripled(numbers); // => [30, 60, 75, 105, 120]
 function filteredAndTripled(numbers: number[]): number[] {
   // write your code here...
-
-  return []; // replace empty array with what you see is fit
+  return numbers.filter(number => number % 5 == 0).map(number => number * 3) 
 }
 
 export { filteredAndSquared, filteredAndTripled };
diff --git a/src/mapping.ts b/src/mapping.ts
index 6f18eef..6b3868f 100644
--- a/src/mapping.ts
+++ b/src/mapping.ts
@@ -11,8 +11,7 @@ const numbers = [10, 13, 20, 25, 38, 35, 40];
 // squaredNumbers(numbers); // => [100, 169, 400, 625, 1444, 1225, 1600]
 function squaredNumbers(numbers: number[]): number[] {
   // write your code here...
-
-  return []; // replace empty array with what you see is fit
+  return numbers.map(number => number ** 2)
 }
 
 // `doubledNumbers` function that:
@@ -22,8 +21,7 @@ function squaredNumbers(numbers: number[]): number[] {
 // doubledNumbers(numbers); // => [20, 26, 40, 50, 76, 70, 80]
 function doubledNumbers(numbers: number[]): number[] {
   // write your code here...
-
-  return []; // replace empty array with what you see is fit
+  return numbers.map(number => number * 2)
 }
 
 export { squaredNumbers, doubledNumbers };