The product of two co-prime numbers is $117$. Find their LCM.

A courtyard is $6$ $\mathrm{m}$ long and $5$ $\mathrm{m}$ wide. Arhan covers the courtyard with square tiles without cutting them. The largest size of each tile used by Arhan is $1 {\mathrm{m}}^2$. Find the number of tiles required?

Three ropes of lengths $6$ $\mathrm{m}$ $30$ $\mathrm{cm}$, $5$ $\mathrm{m}$ $85$ $\mathrm{cm}$ and $3$ $\mathrm{m}$ $60$ $\mathrm{cm}$, respectively, are cut into smaller pieces of equal length. What will be the greatest possible length of each piece?