- Login to Your Blogger Account
- On Your Dashboard, Click on Layout (see below shown picture for further assistance)

- Now Click on HTML (see below shown picture for further assistance)
- Now Check the box of Expand Widget Templates (see below shown picture for assistance)

- Convert Your Google Adsense Code into XML Format using http://centricle.com/tools/html-entities/(This does not violate Google Adsense TOS)
- Now Search For <data:post.body/>
Paste the Code given below before and after <data:post.body/>
<b:if cond='data:blog.pageType == "item"'>
GOOGLE ADSENSE CONVERTED CODE HERE
</b:if>