Question

Two friends Rajat and Rajesh are 12.5 km apart. If they travel in opposite directions, they meet each other after half an hour and if they travel in the same direction, the meet after 2.5 hours. If Rajeh travels faster , what is his speed?

Answer 1

Two persons p and q are 12.5 km apart.
Where p is Rajat and q is Rajesh.

if they travel towards each other they meet after 1/2 hour and

if they travel in the same direction,they meet after 2 1/2 hours.

if p travels faster than q what is his speed

:

let p = p's speed

let q = q's speed

:

Towards each other equation, their dist adds up to 12.5

Write dist equation; dist = time * speed

.5p +.5q = 12.5

:

Going the same way equation, p's dist - q's dist = 12.5

2.5p - 2.5q = 12.5

:

Multiply the first equation by 5, add to the above equation

2.5p + 2.5q = 62.5

2.5p - 2.5q = 12.5

--------------------addition eliminates q, find p

5p = 75

p = 75/5

p = 15 km/hr is p's speed