Q6. 
Among four persons Prince, Queen, Raj and Sashi. Prince takes thrice as much time as Queen to complete a piece of work. Queen takes thrice as much time as Raj and Raj takes thrice as much time as Sashi to complete the same work. One group of three of the four men can complete the work in 13 days while another group of three can do so in 31 days. Which is the group that takes 13 days? 
A.  Prince, Queen, Raj 

B.  Prince, Queen, Sashi 

C.  Queen, Raj, Sashi 

D.  Prince, Raj, Sashi 
Q7. 
Pipe A fills a tank of 700 litres capacity at the rate of 40 litres a minute. Another pipe B fills the same tank at the rate of 30 litres a minute. A pipe at the bottom of the tank drains the tank at the rate of 20 litres a minute. If pipe A is kept open for a minute and then closed and pipe B is kept open for a minute and then closed and then pipe C is kept open for a minute and then closed and the cycle repeated, how long will it take for the empty tank to overflow? 
A.  42 minutes 

B.  14 minutes 

C.  39 minutes 

D.  None of these 
Q8. 
A man takes 20 days to reach the point $B$ under normal circumstances. But, due to the increasingly hostile weather conditions the distance they travel every day reduces by $20%$. In how many days would the man reach the point $B$, taking into consideration weather conditions? 
A.  25 

B.  50 

C.  100 

D.  None of these 
Q9. 
A tank is fitted with 8 pipes, some of them that fill the tank and others that are waste pipe meant to empty the tank. Each of the pipes that fill the tank can fill it in 8 hours, while each of those that empty the tank can empty it in 6 hours. If all the pipes are kept open when the tank is full, it will take exactly 6 hours for the tank to empty. How many of these are fill pipes? 
A.  2 

B.  4 

C.  6 

D.  8 
Q10. 
There are four varieties of pipes Pipe $A$, Pipe $B$, Pipe $C$ and Pipe $D$. Each pipe can be either an inlet pipe or an outlet pipe but cannot be both. there are 5 tanks of equal volume. Tank $P$ is filled by Pipe $A$ and Pipe $B$ Tank $Q$ is filled by Pipe $A$ and Pipe $C$ Tank $R$ is filled by Pipe $A$ and Pipe $D$ Tank $S$ is filled by Pipe $B$ and Pipe $C$ Tank T is filled by Pipe $C$ and Pipe $D$ Time taken for the first 3 tanks ($P$, $Q$ and $R$) to get filled are in the ratio $1:2:4$ and the time taken for the $S$ and $T$ tanks to be filled are in the ratio $7:10$. Find the outlet pipes among the 4 varieties. 
A.  Pipes $C$ and $D$ 

B.  Pipe $D$ 

C.  Pipes $A$ and $B$ 

D.  Pipe $A$ 