Line Plots · Easy problem

A line plot shows the lengths of some pieces of yarn, in inches. Above $\dfrac{1}{8}$ there are $2$ X's, above $\dfrac{3}{8}$ there is $1$ X, above $\dfrac{5}{8}$ there are $4$ X's, and above $\dfrac{6}{8}$ there are $2$ X's. What is the difference between the longest piece and the shortest piece, in inches?