In order to calculate the number wanted, let's use the values of R = 0.75 (that is, 75%) and A = 165 in the given formula. Then, we solve it for B.
So we have:
[tex]\begin{gathered} 0.75\cdot B=165 \\ B=\frac{165}{0.75} \\ B=220 \end{gathered}[/tex]Therefore the number wanted is 220.