The Sensex opened with a gain of 280 points on Monday, boosted by another investment in Reliance Jio which sold 0.15 percent stake to Qualcomm Ventures and got investments worth Rs 730 crore. With this investment, Reliance has so far sold 25.24 percent stake in Jio Platforms Ltd and has raised a total of Rs 118,318.45 crore from 12 investors so far. Reliance owner Mukesh Ambani has accepted investments of more than Rs 1.18 trillion in Jio since April.