diff --git a/01_helloWorld/helloWorld.js b/01_helloWorld/helloWorld.js
index df27036e279..b542f3ba428 100644
--- a/01_helloWorld/helloWorld.js
+++ b/01_helloWorld/helloWorld.js
@@ -1,5 +1,5 @@
 const helloWorld = function() {
-  return ''
+  return 'Hello, World!'
 };
 
 module.exports = helloWorld;
diff --git a/02_addNumbers/addNumbers.js b/02_addNumbers/addNumbers.js
index 7e04e40aec8..e5dc8316226 100644
--- a/02_addNumbers/addNumbers.js
+++ b/02_addNumbers/addNumbers.js
@@ -4,7 +4,7 @@ function addNumbers() {
 
   let result;
 
-  result = "a" + "b"; // <------ EDIT THIS LINE
+  result = a + b; // <------ EDIT THIS LINE
 
   return result;
 }
diff --git a/03_numberChecker/numberChecker.js b/03_numberChecker/numberChecker.js
index 9efcef5928b..531d6abc77e 100644
--- a/03_numberChecker/numberChecker.js
+++ b/03_numberChecker/numberChecker.js
@@ -1,8 +1,8 @@
 function numberChecker(number) {
-  if (number === 6) {
-    return true;
-  } else {
+  if (number >= 10) {
     return false;
+  } else {
+    return true;
   }
 }
 
diff --git a/04_mathEquations/mathEquations.js b/04_mathEquations/mathEquations.js
index 6df7f783d44..7861dcfdf94 100644
--- a/04_mathEquations/mathEquations.js
+++ b/04_mathEquations/mathEquations.js
@@ -1,9 +1,9 @@
 const a = 1 - 1 // Freebie!!! This is the answer to "one minus one"
-const b = "one plus eight"
-const c = "22 times three"
-const d = "the *remainder* of 5/4"
-const e = "the variable 'b' minus 17"
-const f = "the sum of the previous five variables"
+const b = 1+8 // "one plus eight"
+const c = 22 * 3 //"22 times three"
+const d = 5%4 // "the *remainder* of 5/4"
+const e = b-7 // "the variable 'b' minus 17"
+const f = a+b+c+d+e // "the sum of the previous five variables"
 
 // Do not edit below this line
 module.exports = {a, b, c, d, e, f}
diff --git a/05_joinStrings/joinStrings.js b/05_joinStrings/joinStrings.js
index 9421ab63a79..63e7afdaa93 100644
--- a/05_joinStrings/joinStrings.js
+++ b/05_joinStrings/joinStrings.js
@@ -9,9 +9,12 @@
 
 // Add your code right below, good luck!
 
+const firstName = "Carlos";
+const lastName = "Stevenson";
+const thisYear = 1965;
+const birthYear = 1947;
 
-
-
+const greeting = "Hello! My name is " + firstName + lastName + " and I am " + (thisYear - birthYear) +"years old."
 
 // Do not change this
 module.exports = {