A person covers a distance of 52 km in 7 hrs . Some part of this journey is covered on foot at the speed of 7 km/hr and the rest by cycle at the speed of 8 km/hr. Find the distance covered on foot .

28 km

Distance = Speed × Time 

Total Distance = 52 km 

Total Time taken = 7 hours 

Let the time he traveled on foot be x hours with speed 7 km/hr 

And time he traveled by bicycle is ( 7 - x ) hours with speed 8 km/hr 

According to question , 

7 × x + 8 × ( 7 - x ) = 52 

7x + 56 - 8x = 52 

x = 4 hours  

So ,  distance traveled by foot = 7  ×  4 = 28 km