Question

two boys start runing towards each other from two points, they are 120m apart. One runs with a speed of 5m/s and other with a speed of 7m/s. When and where do they meet each other from 1st point

Answer 1

Total distance covered by both boys must equal 120m
We need to find the time it takes for them to meet.

--> 5t + 7t = 120

--> 12t = 120
--> t = 10s 

Now find distance covered by boy running at 5 m/s
--> d = 5(10)
--> d = 50m

Therefore they meet at 50m from the first boy's end.

Answer 2

Let A and B are two bodies start moving each other . speed of body A is 5m/sec and speed of body B is 7m/sec .

Let at point C , they meet each other and t is meeting time .

A===========C =============B

we know ,
distance = speed × time

distance covered by A = 5 × t = 5t m
distance covered by B = 7 × t = 7t m

for they meet each other condition is
distance covered by A + distance covered by B = intial distance between A and B

5t + 7t = 120 m

12t = 120 m

t = 10 sec

hence, bodies meet each other at t = 10s

distance covered by A = 5t = 5×10 = 50m distance covered by B =7t =7×10 = 70m

hence, 50m distance from 1st point they meet each other.