Question

an object travels 16m in 4s. and another in 16m in 2s. find the average speed ?

Answer 1

average speed = total distance
                         total time
                     = 16+16
                         4+2
                     = 32/6
                      =5.33m/s

Answer 2

Total distance travelled = (16+16)m =32 m
Total time taken = (4+2) secs = 6 secs

$Average Speed= \frac{Total distance travelled}{Total time taken}$
Average speed = $\frac{32}{6}$
Average Speed = 5.333 m/sec