How to open a random image

I have a new doubt and this has been the best place to find answers, since Ja agradeco.
My problem and the following, I am doing a school questionnaire for my child.
And one simple thing, at least it should be. A question with 3 answers, one right and two wrong. By clicking on the right answer a commemorative image appears.
I would like this image to be random so as not to become tiresome.
I'm using the next 

function SIM() {
    var oImg = document.createElement("img");
    oImg.setAttribute('src', 'img/certo.jpg');
    oImg.setAttribute('alt', 'na');
    oImg.setAttribute('height', '200px');
    oImg.setAttribute('width', '200px');
    document.body.appendChild(oImg);
}

And no body 

<button id="SIM" onclick="SIM();">6</button>

I would like to have 10 images of celebration and I was thinking of something like 

function SIM() {  
    var oImg = document.createElement("img");  
    oImg.setAttribute('src', '**NUMERO DE 1~10 ALEATORIO**.jpg');  
    oImg.setAttribute('alt', 'na');  
    oImg.setAttribute('height', '200px');  
    oImg.setAttribute('width', '200px');  
    document.body.appendChild(oImg);  
}

Is there any way to achieve this???
Thank you very much

Author: Sergio, 2017-07-02
Source

1 answers

To create a random number you can do Math.round(Math.random() * 10).

function SIM() {  
    var oImg = document.createElement("img");  
    var nr = Math.round(Math.random() * 10);
    oImg.setAttribute('src', nr + '.jpg');  
    oImg.setAttribute('alt', 'na');  
    oImg.setAttribute('height', '200px');  
    oImg.setAttribute('width', '200px');  
    document.body.appendChild(oImg);  
}
 1
Author: Sergio, 2017-07-02 14:06:52