Question

A person left a city P to city Q in a car at 8.00am. He travelled at a speed of 90kmph for 3 hours. After that the speed was reduced to 80kmph. If the distance between the cities is 510 kms.,at what time did he reach city Q ?

Answer 1

Answer:

02:00 P.M.

Step-by-step explanation:

Speed1 = 90kmph

Time1 = 3 hrs

Dist1 = s*t

         =90*3

         =270 km.

Speed2 = 80kmph

Dist2 = Dist. left = 510-270

                             =240 km

Time2 = 240/80

           =3 hrs

Total time = 3+3

                  = 6 hrs

Time reached =

                        02:00 P.M.

Answer 2

Answer:2 pm

Step by step:-

Relative speed=90+80=170

Now time=D/S

=510/170

=3 hr

So,they travel for 3 hour already..

So, total time =3+3=6hr.

Add this 6 hr. In 8:00 am

So time=8+3+3=2 pm