On a 300 km long racing track, three bikes — A, B, and C take part in a race. Initially, their speeds are 50 km/hr for Bike A, 40 km/hr for Bike B, and 60 km/hr for Bike
C. After the first 2 hours of racing, their speeds are altered as follows: Bike A adopts a new speed which is 25% more than Bike C’s speed at that moment. Bike B increases its speed by 10% compared to its original speed. Bike C reduces its speed to 80% of Bike A’s original speed. Find the time gap (in minutes) between the bikes that finished first and second.

Total Track Length = 300 km Initial Speeds: Bike A = 50 km/hr Bike B = 40 km/hr Bike C = 60 km/hr After 2 hours, speeds are changed. Distance Covered in First 2 Hours A: 50 × 2 = 100 km B: 40 × 2 = 80 km C: 60 × 2 = 120 km Remaining Distance: A → 300 − 100 = 200 km B → 300 − 80 = 220 km C → 300 − 120 = 180 km New Speeds After 2 Hours Bike C = Reduces speed to 80% of Bike A’s original speed. [80% of 50 = 40] New speed of C = 40 km/hr Bike A: Adopts a speed 25% more than Bike C’s speed at that moment.
(At that moment, C’s speed = 40 km/hr) 40 + 25% of 40 = 40 + 10 = 50 New speed of A = 50 km/hr Bike B: Increases speed by 10% of original speed. [40 + 10% of 40 = 40 + 4 = 44] New speed of B = 44 km/hr Time to Cover Remaining Distance Bike A = 200 ÷ 50 = 4 hours Total time = 2 + 4 = 6 hours Bike C = 180 ÷ 40 = 4.5 hours Total time = 2 + 4.5 = 6 hr 30 min Bike B = 220 ÷ 44 = 5 hours Total time = 2 + 5 = 7 hours Time Gap Between First and Second = 6 hrs 30 min − 6 hrs = 30 minutes