Image alignment

try this in your css:

img.centered {
    display: block;
    margin-left: auto;
    margin-right: auto;
	border: 0px;
}

img.alignright {
    padding: 4px;
    margin: 0 0 2px 7px;
    display: inline;
	border: 0px;
}

img.alignleft {
    padding: 4px;
    margin: 0 7px 2px 0;
    display: inline;
	border: 0px;
}

.alignright {
    float: right;
}

.alignleft {
    float: left;
}

Not worked, as you can see, have I made mistake? see code below
#content img {
margin: 0;
height: auto;
max-width: 940px;
width: auto;

}
#content .attachment img {
max-width: 900px;
}
#content .alignright,
#content img.alignright {
padding: 4px;
margin: 0 0 2px 7px;
display: inline;
border: 0px;
}
#content .alignleft,
#content img.alignleft {
padding: 4px;
margin: 0 7px 2px 0;
display: inline;
border: 0px;
}
#content .aligncenter,
#content img.centered {
display: block;
margin-left: auto;
margin-right: auto;
border: 0px;
}
#content img.alignleft {
float: left;
}
#content img.alignright {
float: right;
}
#content img.aligncenter {
margin-bottom: 12px;

twenty ten already comes with the styles for image alignment – therefore my guess, that you have changed something in style.css of the theme, that stops the application of styles (happens easily, even with small typing errors)

can you re-post a link to your site?

https://www.sharpehairandbeauty.co.uk

#content {
	margin: 0 100px 0 20px;
}

find this style in style.css and set the right margin to 0 (zero), i.e. change the 100px to 0px

if this makes problems in other pages, then don’t make the change, and add a new style after the one above:
.home #content { margin-right: 0px; }