Q6. 
Rajesh travelled from city $A$ to city $B$ covering twice as much distance in the second part as he did in the first part of this journey. His speed during the second part was twice as that of the speed during the first part of the journey. What is his average speed of journey during the entire travel? 
A.  His average speed is the harmonic mean of the individual speeds for the two parts. 

B.  His average speed is the arithmetic mean of the individual speeds for the two parts. 

C.  His average speed is the geometric mean of the individual speeds for the two parts 

D.  Cannot be determined. 
Q7. 
A train traveling at 100 kmph overtakes a motorbike traveling at 64 kmph in 40 seconds. What is the length of the train in meters? 
A.  1777 meters 

B.  1822 meters 

C.  400 meters 

D.  800 meters 
Q9. 
In a 500 m race Dishu beats Abhishek by 100 m or 5 seconds. In another race on the same track at the same speeds. Abhishek and Prashant start at one end while Dishu starts at the opposite end. How many metres would Abhishek have covered, by the time Dishu meets Prashant given that Dishu's speed is 10 m/sec more than that of Prashant. 
A.  200 m 

B.  225 m 

C.  250 m 

D.  275 m 
Q10. 
The speed of a motor boat itself is 20 km/h and the rate of flow of the river is 4 km/h. Moving with the stream the boat went 120 km. What distance will the boat cover during the same time going against the stream? 
A.  80 km 

B.  180 km 

C.  60 km 

D.  100 km 