diff --git a/functions.js b/functions.js
index f06bcee..de50f95 100644
--- a/functions.js
+++ b/functions.js
@@ -4,6 +4,11 @@
  * @return {string} the number as a string
  */
 
+ function numberToString(num){
+ 	return num + '';
+ }
+
+
 
 /**
  * Adds one to a given number.
@@ -11,12 +16,18 @@
  * @return {number}
  */
 
+function increase(num){
+	return num + 1;
+}
 
 /**
  * Subtracts one from a given number.
  * @param {number} n
  * @return {number}
  */
+ function decrease(num){
+ 	return num - 1;
+ }
 
 
 /**
@@ -25,6 +36,9 @@
  * @param {number} y
  * @return {number} the sum
  */
+function add(x,y){
+	return x + y;
+}
 
 
 /**
@@ -34,6 +48,10 @@
  * @return {number} the difference
  */
 
+ function subtract(x,y){
+ 	return x - y;
+ }
+
 
 /**
  * Multiplies two numbers.
@@ -42,6 +60,10 @@
  * @return {number} the product
  */
 
+ function multiply(x,y){
+ 	return x * y;
+ }
+
 
 /**
  * Divides the first number by the second.
@@ -50,6 +72,10 @@
  * @return {number} the quotient
  */
 
+ function divide(x,y){
+ 	return x / y;
+ }
+
 
 /**
  * Multiplies a number by itself.
@@ -57,6 +83,10 @@
  * @return {number} squared
  */
 
+ function square(x){
+ 	return x * x;
+ }
+
 
 /**
  * Performs a mathematical operation on two numbers.
@@ -67,6 +97,28 @@
  * @return {number} the result
  */
 
+var result;
+ var equation;
+
+ function calculate (operation, x,y){
+ 	if (operation === "add"){
+ 		result = add(x,y);
+ 		equation = x + " + " + y + " = " + result;
+ 	}else if (operation === "subtract"){
+ 		result = subtract(x,y);
+ 		equation = x + " - " + y + " = " + result;
+ 	}else if (operation === "multiply"){
+ 		result = multiply(x,y);
+ 		equation = x + " * " + y + " = " + result;
+ 	}else if (operation === "divide"){
+ 		result = divide(x,y);
+ 		equation = x + " / " + y + " = " + result;
+ 	}
+ 	
+
+ 	console.log(equation);
+ 	return(result);
+ }
 
 /**
  * Returns true if `a` is greater than `b`.
@@ -75,6 +127,10 @@
  * @return {boolean} `a` is larger than `b`
  */
 
+ function isGreaterThan(a,b){
+ 	return a > b;
+ }
+
 
 /**
  * Returns true if `a` is less than `b`.
@@ -82,6 +138,9 @@
  * @param {number} b
  * @return {boolean} `a` is smaller than `b`
  */
+ function isLessThan(a,b){
+ 	return a < b;
+ }
 
 
 /**
@@ -91,6 +150,11 @@
  * @return {boolean} the numbers are equal
  */
 
+ function areEqual(a,b){
+ 	return a === b;
+ }
+
+
 
 /**
  * Returns the smallest value of two numbers.
@@ -99,6 +163,10 @@
  * @return {number} the smallest number
  */
 
+ function minimum(x,y){
+ 	var z = Math.min(x, y);
+ 	return z;
+ 	}
 
 /**
  * Returns the largest value of two numbers.
@@ -107,6 +175,11 @@
  * @return {number} the largest number
  */
 
+ function maximum(x,y){
+ 	var z = Math.max(x,y);
+ 	return z;
+ }
+
 
 /**
  * Returns true if `n` is even.
@@ -114,6 +187,10 @@
  * @return {boolean} the number is even
  */
 
+ function isEven(n){
+ 	return n % 2 === 0;
+ }
+
 
 /**
  * Returns true if `n` is odd.
@@ -121,6 +198,9 @@
  * @return {boolean} the number is odd
  */
 
+function isOdd(n){
+	return n % 2 !== 0;
+}
 
 /**
  * Returns a letter grade.
@@ -133,6 +213,20 @@
  * @param {number} total maximum possible score
  * @return {string} the score represented as a letter grade
  */
+ function letterGrade(score, total){
+ 	var percentage = score/total * 100;
+ 	if (percentage < 60) {
+		return "F";
+	} else if (percentage < 70) {
+		return "D";
+	} else if (percentage < 80) {
+		return "C";
+	} else if (percentage < 90) {
+		return "B";
+	} else {
+		return "A";
+	}
+};
 
 
 /**
@@ -143,6 +237,17 @@
  * @return {object} restaurant
  */
 
+ function incrementReviews(restaurant){
+ 	if(restaurant.reviews){
+ 		restaurant.reviews += 1;
+	}else{
+		restaurant.reviews = 1;
+	}
+
+	return restaurant;
+
+ }
+
 
 /**
  * Joins two strings with a space.
@@ -151,6 +256,10 @@
  * @return {string} joined the words joined with a space
  */
 
+ function combine(word1,word2){
+ 	return word1 + " " + word2;
+ }
+
 
 /**
  * Returns a circle object with the properties `circumference` and `area`.
@@ -160,3 +269,17 @@
  * @return {object} circle
  */
 
+
+ function createCircle(radius){
+ 	var circle = {
+ 		area: (radius * radius * Math.PI),
+ 		circumference: (2 * radius * Math.PI)
+ 	};
+
+ 	return circle;
+
+ }
+
+
+
+