source?

Possible value for a and c = 2 hence, we substitute it in our given Qty A and B

\frac{a}{b+1}= \frac{c}{d+2}\\
\frac{2}{b+1}=\frac{2}{d+2}

Now, it’s given that 0<b<d thus, we shouldn’t sub. 3 as a potential value for b and d but let’s do it anyways

\frac{2}{3+1}= \frac{2}{3+2} \text{ or } \frac{2}{4} = \frac{2}{5}

Here, **Qty A > QtyB**. Now, as we’re given 0<b<d let’s make d=3.1 and b will remain 3 and a=c= 2

\frac{2}{4} = \frac{2}{5.1}

Here, also we get **Qty A > QtyB** and as we keep increasing the value of d our **Qty B** will get smaller and smaller hence, **Qty A > QtyB**