It depend and what you want but fixed width and high margin isn’t the solution, you need another wrapper on your image for center them, and adjust your CSS: 
<div id="responsivearea">
    <div class="img-center">
        <img class="wp-image-2520 alignleft" src="http://www.inspuratesystems.com/nayajeevan/wp-content/uploads/2014/11/good-employer.png" alt="good employer" width="201" height="199" /> 
        <img class="wp-image-2521 alignleft" src="http://www.inspuratesystems.com/nayajeevan/wp-content/uploads/2014/11/gift-of-health.png" alt="gift of health" width="201" height="199" /> 
        <img class="wp-image-2522 alignleft"  src="http://www.inspuratesystems.com/nayajeevan/wp-content/uploads/2014/11/Change-maker.png" alt="Change maker" width="201" height="199" />
    </div>
</div>
and the css :
#responsivearea{
    max-width: 900px; 
    margin: 0 auto; 
    clear: none;
    width: 100%;
    text-align: center;
}
.img-center{
    display:inline-block;
}
.alignleft{
    float: left; 
    clear: none;
}
here a fiddle : http://jsfiddle.net/x9jjqugd/1/
Hope I help !
0
solved Making div responsive with margin 0 auto in it