Question

A man walks for 5 km/hr for 1 km and 7 km/hr for next 1 km. What is his average speed for the walk of 2 km?

-5.8 km/hr

-6.0 km/hr

-2.0 km/hr

-1.0 km/hr

Thank you very much!!

Answer 1

Btw the answers I gave above are positive values, not negative values. Sorry for any confusion.

Answer 2

d1 = V1*t1 = 1 km.
t1 = 1/V1 = 1/5 = 0.20 h.

t2 = 1/V2 = 1/7 = 0.143 s.

V=d/(t1+t2)=2km/(0.20+0.143)h=5.8 km/h.