Defending champions West Indies kept their hopes alive of a semi-final berth with a resounding 73-run thrashing of hosts Bangladesh in a Group 2 Super 10 match of the ICC World Twenty20 in Mirpur tonight.Chasing a target of 172, Bangladesh's inept batting performance once again brought about their downfall as they bundled out out for a paltry 98 in 19.1 overs.The margin of victory also ensured that West Indies improved their net run-rate radically having lost to India in their opening league game with two balls to spare.Chris Gayle and Dwayne Smith gave West Indies a 97 run opening stand after being invited to bat by Bangladesh.Now, India will take on Bangladesh in their next group encounter at Mirpur on Friday at 7 pm.