Question

(1) Define average speed. (2) A bus travels a distance of 120 km with a speed of 40 km and returns with a speed of 30 km/h. calculate the average speed for the entire journy.​

Answer 1

Answer:

average speed is the ratio of the total distancee covered to the total time taken.

Mathematecally,

Avg. Speed = $\frac{Total Distance}{Total Time}$

in the question

he cover 120 km with 40km/hr

=> time taken = $\frac{120}{40}$ = 3hrs

and another 120km with 30km/hr

=> time taken = $\frac{120}{30}$ = 4hrs

now,

avg speed = $\frac{Total Distance}{Total Time}$

                 =  $\frac{120 + 120}{3+4}$

                 = $\frac{240}{7}$

                 = 34.2857 km/hr

hope this helps :):):):)