If a man walk 20 km. at 4 km/hr. and he will be late by 35 min .If he walks at double speed. Then how early from the fixed time will he reach?

Distance = 20 km. Speed 1 = 4 km/hr gives time = 5 hours. Speed 2 = 8 km/hr gives time = 2.5 hours. Difference = 5 - 2.5 = 2.5 hours = 2 hours 30 minutes. Since he was 35 minutes late at speed 1, at speed 2 he would be 35 + (2 hours 30 minutes) = 3 hours 5 minutes early... Wait, that's not an option. Let me recalculate: If 5 hours makes him 35 min late, the fixed time is 4 hours 25 min. At 2.5 hours, he reaches 4:25 - 2:30 = 1 hour 55 min early. Option C is correct.