Consider the given figure in which PQ is a line segment drawn through the mid-point P of line AB, such that PQ || BC

By using the proportionality theorem, we obtain
\(\frac{AQ}{QC}=\frac{AP}{PB}\)
\(\frac{AQ}{QC}=\frac{1}{1}\)
\(\Rightarrow\)AQ = QC
Or, Q is the midpoint of AC

In the adjoining figure, \( AP = 1 \, \text{cm}, \ BP = 2 \, \text{cm}, \ AQ = 1.5 \, \text{cm}, \ AC = 4.5 \, \text{cm} \) Prove that \( \triangle APQ \sim \triangle ABC \).
Hence, find the length of \( PQ \), if \( BC = 3.6 \, \text{cm} \).