Question

Ajay walked at an average speed of 8 km per hour for 45 minutes and then walked at an average speed of 12 kilometre per hour for 40 minutes.What was his average speed for the whole journey?

Answer 1

$(8 \times \frac{3}{4} )km + (12 \times \frac{2}{3} )km \\ = 6km + 8km \\ = 14km$
Total distance in 40mins+45mins=85/60hrs=17/12hrs
$14km \times \frac{12}{17} = \frac{164km}{17km}$

This is average speed.z

Answer 2

Answer:

5.64 km/hr

Step-by-step explanation:

Ajay walked at an average speed of 8 km per hour for 45 minutes

Speed =8 km/hr

Time = 45 minutes = $\frac{45}{60} hr$

Distance = Speed * time = $8 \times \frac{45}{60} = 6$

He walked at an average speed of 12 kilometre per hour for 40 minutes

Speed = 12 km/hr

Time = 40 minutes = $\frac{40}{60} hr$

Distance = Speed * time = $12 \times \frac{40}{60} = 8$

Total distance = 8+6 = 14 km

Total Time = $\frac{45}{60} +\frac{40}{60}=\frac{85}{60}$

Average speed = Distance/Time =$\frac{8}{\frac{85}{60}} = 5.64 km/hr$

Hence his average speed for the whole journey is 5.64 km/hr