An object travels 24 m with a speed of 4 metre per second and another 32 m with a speed of 8 metre per second. The average speed of the object is

Time travel to cover 24 m with the speed of 4 metre per second,
t₁ = 24/4 = 6 s
Time travel to cover 32 m with the speed of 8 metre per second,
t₂ = 32/8 = 4 s
Average speed = Total distance/total time = 24 + 32/ t₁ + t₂
= 56/6+4
= 5.6 m/s