Updated from 4:36 p.m. EST to provide comments from conference call.NEW YORK ( TheStreet) -- LinkedIn ( LNKD) shares jumped after the company posted better-than-expected first-quarter results, as revenue at its biggest unit more than doubled. Mountain View, Calif.-based LinkedIn reported earnings of 15 cents per share on $188.50 million in revenue for the March-ended period. Analysts polled by Thomson Reuters were expecting earnings of 9 cents per share on $178.58 million in revenue. Sales at Hiring Solutions, its biggest segment, soared 121% to $102.6 million. It accounted for 54% of revenue, up from 49% a year earlier. On the conference call, LinkedIn said this was the seventh straight quarter with revenues doubling.