The number of watches sold in Town Y increased by what per cent from February to May?

Answer: Option D

Number of Watches sold in Town Y in February = 120
Number of Watches sold in Town Y in May = 230
Required percentage increase
$$\begin{array}{rl}& =\frac{230-120}{120}\times 100\\ & =\frac{110}{120}\times 100\\ & =\frac{110\times 5}{6}\\ & =\frac{275}{3}\\ & =91\frac{2}{3}\%\end{array}$$