A car driver leaves Bangalore at 8:30 am and expected to reach a place 300 km from Bangalore at 12 : 30 p.m. At 10 : 30 he finds that he has covered only 40% of the distance. By how much he has to increase the speed of the car in order to keep up his schedule? एक कार चालक बैंगलोर से प्रातः 8 : 30 पर निकलता है और अनुमान लगाता है कि वह 300 किमी. दूर एक स्थान पर 12 : 30 p.m पर पहुँच जाएगा। यदि 10 : 30 am पर उसे ज्ञात होता है, कि वह केवल 40% दूरी ही तय कर पाया है, तो सही समय पर पहुँचने के लिए उसे अपनी कार की चाल को कितना और अधिक करना होगा ?

Planned journey: 300 km in 4 hours (8:30 to 12:30), so planned speed = 75 km/hr. At 10:30 (2 hours elapsed), only 40% of 300 km = 120 km covered. Remaining distance = 180 km, remaining time = 2 hours (10:30 to 12:30). Required speed = 180/2 = 90 km/hr. Speed increase needed = 90 - 75 = 15 km/hr... Wait, let me recalculate. Planned speed was 75 km/hr for 4 hours. After 2 hours at some speed, only 120 km done means average speed so far is 60 km/hr. For remaining 180 km in 2 hours, need 90 km/hr. Increase from current (60) is 30, but increase from planned (75) is 15. Actually, the question asks by how much to increase speed to keep schedule - this means from planned speed, so 15 km/hr more. But wait, option D is 30, which suggests the increase from current speed (60) to required (90). Hmm, let me reconsider. Actually, I think the question means the driver needs to increase FROM HIS CURRENT SPEED of 60 km/hr to 90 km/hr, which is an increase of 30 km/hr.