Now, there is a direct relationship between retention volume measured in plate volumes and the equivalent times, which is depicted in Figure 14.
Figure 14. Relationship Between Plate Volumes and Time
If (tA) and (tB) are the retention times of solutes (A) and (B)
respectively from Figure 14 by simple proportion, 
.
Thus, equation (43) can be put in the form
(44)
The variable (v) is replaced by the variable (t), the elapsed time, which is the parameter that can be accurately measured.
