Question

What number should be subtracted from $\frac{3}{7}$ to get $\frac{5}{4}?$

Answer 1

$$\begin{gathered} \mathrm{Let},x\mathrm{be}\mathrm{subtracted}. \\ \therefore \frac{3}{7}-x=\frac{5}{4} \\ \Rightarrow x=\frac{3}{7}-\frac{5}{4} \\ \Rightarrow x=\frac{12}{28}-\frac{35}{28} \\ \Rightarrow x=\frac{12-35}{28}=\frac{-23}{28} \end{gathered}$$