There are 100 people in a line. Sandy is the 40th person and Enai is the 67th person. If person on line is chosen at random, what is the probability that the person is standing between Sandy and Enai ?

Question

$\begin{array}{1 1} (a)\; \large\frac{13}{50} \\ (b)\; \large\frac{16}{50} \\ (c)\; \large\frac{23}{50} \\ (d)\;\large\frac{13}{70}\end{array}$