Mathematics - Functions Question with Solution | TestHub

Let$X$be a set with exactly$5$elements and$Y$be a set with exactly$7$elements. If$\alpha$is the number of one-one functions from$X\to Y$and$\beta$is the number of onto functions from$Y\to X$, then the value of$\frac{1}{5!}\left(\beta -\alpha \right)$is _____-.