First create a child theme of twenty eleven. After that go to the style.css file and find line 723. Line 723 should look like this:
.entry-title {
clear: both;
color: #222;
font-size: 26px;
font-weight: bold;
line-height: 1.5em;
padding-bottom: .3em;
padding-top: 15px;
}
Replace the previous batch of code with this one:
.entry-title {
text-align: right;
clear: both;
color: #222;
font-size: 26px;
font-weight: bold;
line-height: 1.5em;
padding-bottom: .3em;
padding-top: 15px;
}
Please let me know if this works or if you need more help. By the way, are you trying to make your theme work with right to left languages, or are you just trying to do this little tweak?