Formula: After meeting each other, two trains of speeds x km/hr and y km/hr respectively complete their journeys in t1 and t2 , then (x/y)2=t2 /t1 Calculation: Let t1 =25 and t2 = 64 Let speed other car be x km/hr respectively, According to the question (8/x)2 = (64/25) ⇒ 8/x = √64/25 ⇒ 8/x = 8/5 ⇒ x = 8 × (5/8) ⇒ x = 5 km/hr ∴ Speed of other car was 5 km/hr.