A person goes from P to Q in 8 hours. He starts from Pat 8 a.m. Another person goes from Q to P in 12 hours. He starts from Q at 9 a.m. At what time will they meet?

1:12 p.m

Time required by 1st person to cover distance b/w = 8 hours

Time required by 2nd person to cover distance b/w = 12 hours

We know ,

Speed is inversely proportional to time .

Ratio               1st     :      2nd

Time                 8      :        12

Speed               12     :        8

Let distance b/w P & Q = 96 km

Distance covered by 1 st person till 9:00 am = 12 × 1 = 12 km

Remaining distance = 96 - 12 = 84km

Relative speed = 12 + 8 = 20 km/h

(when moves in opposite direction )

Time = \(\frac{Distance}{Speed }\)

= \(\frac{84}{20}\) = 4 hours 12 minutes

So , Both of them will meet at = 9:00 am + 4 hours 12 minutes =  1:12 pm