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![sergio verdeza](https://uploads.teamtreehouse.com/production/profile-photos/588352/micro_sergio_verdeza.jpg)
sergio verdeza
Courses Plus Student 10,765 PointsModify the Car's prototype to have 'wheels' set to 4. Hello, having trouble with this question? Help.......
var carPrototype = { model: "generic", currentGear: 0,
increaseGear: function() {
this.currentGear ++;
},
decreaseGear: function() {
this.currentGear--;
}
}
function Car (model) { this.model = model; }
Car.prototype = carPrototype;
Car.prototype.wheels = 4
<!DOCTYPE html>
<html lang="en">
<head>
<title> JavaScript Foundations: Objects</title>
<style>
html {
background: #FAFAFA;
font-family: sans-serif;
}
</style>
</head>
<body>
<h1>JavaScript Foundations</h1>
<h2>Objects: Prototypes</h2>
<script>
var carPrototype = {
model: "generic",
currentGear: 0,
wheels: 4,
increaseGear: function() {
this.currentGear ++;
},
decreaseGear: function() {
this.currentGear--;
}
}
function Car(model) { this.model = model; }
Car.prototype.wheels = 4;
</script>
</body>
</html>
2 Answers
![Madeleine Nyhagen](https://uploads.teamtreehouse.com/production/profile-photos/1628542/micro_SLG_9382-Edit_web.jpg)
Madeleine Nyhagen
2,880 PointsI think you are just doing too much. I was successful using Car.prototype.wheels = 4; but did not add anything directly to the carPrototype variable. I believe my code looked like this:
var carPrototype = {
model: "generic",
currentGear: 0,
increaseGear: function() {
this.currentGear ++;
},
decreaseGear: function() {
this.currentGear--;
}
}
function Car(model) {
this.model = model;
}
Car.prototype = carPrototype;
Car.prototype.wheels = 4;
![chris slaats](https://secure.gravatar.com/avatar/75072824899566520f1673357cffbbb4?s=96&d=https%3A%2F%2Fecs-static.teamtreehouse.com%2Fassets%2Fcontent%2Fdefault_avatar-445fbbabfc8dc9188fb5967fe43322ee0c3e0dd1e10f378bf8343784af5a13eb.webp&r=pg)
chris slaats
5,996 PointsFor this question you don't have to use Car.prototype.wheels = 4; because you have set the Car.prototype = carPrototype already. Then all the question is asking is of you is to change the Car's prototype which you have just set to carPorotypes variable wheels to 4 so it should look like this. Hope that helps
var carPrototype = {
model: "generic",
currentGear: 0,
wheels: 4,
increaseGear: function() {
this.currentGear ++;
},
decreaseGear: function() {
this.currentGear--;
}
}
function Car(model) {
this.model = model;
}
Car.prototype = carPrototype;