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.
Pipes $C$ and $D$
Pipes $A$ and $B$
Error(s) Found !!!