Professional social network LinkedIn will acquire presentation-sharing startup SlideShare for $118.75 million in cash and stock, the company announced today at market close.

LinkedIn will dole out approximately 45 percent cash and approximately 55 percent stock in the transaction.

“Presentations are one of the main ways in which professionals capture and share their experiences and knowledge, which in turn helps shape their professional identity,” said LinkedIn CEO Jeff Weiner, in a statement. “These presentations also enable professionals to discover new connections and gain the insights they need to become more productive and successful in their careers, aligning perfectly with LinkedIn’s mission and helping us deliver even more value for our members. We’re very excited to welcome the SlideShare team to LinkedIn.”

SlideShare was founded in Oct. 2006 and “helps professionals discover people through content, and content through people.” The service’s users have uploaded more than nine million presentations during the life of the service. In March, SlideShare had about 29 million unique vistors, according to comScore.

The acquisition makes a ton of sense for LinkedIn, which is by far the largest business-oriented social network, with 161 million members worldwide. Professionals use the service to connect with other business folks, find new hires, and to read professional-focused news and content. Now it will also have an arm for sharing presentations across the web.

As long as regulators approve the move, the acquisition is expected to close during the second quarter of 2012.