State what numbers will be printed from this flow chart if $X$ is read as (a) $6$, (b) $9$ and (c) $20$. What is the relation between $X$ and the numbers printed?
This flow chart is intended for use with $X$ being a positive integer. What would happen if $X$ were read to be $2.4$? Suggest a simple change to the second decision box to avoid this problem.