Question

please correct answer quickly please please give me​

Answer 1

Answer: 1000/7km/h=142.8km/h

Explanation:

AVERAGE VELOCITY=TOTAL DISPLACEMENT/TIME TAKEN

                  ===>70=$200/\frac{100/50}{100/x}$

===>2x/100=20/7

==>x=1000/7km/h.

so train should travel with 1000/7=142.8km/h speed to cover 100km and to get a average of 70km/h.

HOPE IT WILL HELP YOU..............

THANK YOU.