Question

If 1.5, 4.5, x, 7.5 are in proportion then find the value of x.

Answer 1

$$\begin{gathered} \mathrm{We}\mathrm{know}\mathrm{that}1.5,4.5,x\mathrm{and}7.5\mathrm{are}\mathrm{in}\mathrm{proportion}. \\ \mathrm{Thus},\mathrm{we}\mathrm{have}: \\ \frac{1.5}{4.5}=\frac{x}{7.5} \\ \Rightarrow 11.25=4.5x \\ \Rightarrow x=2.5 \end{gathered}$$