A student multiplied a number with 3/4 instead of 4/3. What is the error percentage?

Answer: Option B

$$\begin{array}{rl}& \frac{3}{4},\frac{4}{3}\\ & \text{LCM of 4, 3}=12\\ & \text{First number}\\ & =\frac{3}{4}\times 12=9\\ & \text{Second number}\\ & =\frac{4}{3}\times 12=16\\ & \text{Error percentage}\\ & =\frac{7}{16}\times 100=43\frac{3}{4}\%=43.75\%\end{array}$$