The traffic lights at three different road crossings change after every $48$ seconds, $72$ seconds and $108$ seconds respectively. If they change simultaneously at $7\mathrm{}\mathrm{a}.\mathrm{m}.$, at what time will they change simultaneously again?

Find the LCM of the following numbers: $9$ and $4$.

Observe a common property in the obtained LCM. Is LCM the product of the given two numbers?

Find the LCM of the following numbers: $12$ and $5$

Observe a common property in the obtained LCM. Is LCM the product of the given two numbers?

Find the LCM of the following numbers: $6$ and $5$.

Observe a common property in the obtained LCM. Is LCM the product of the given two numbers?

Find the LCM of the following numbers: $15$ and $4$.

Observe a common property in the obtained LCM. Is LCM the product of the given two numbers?

Find the LCM of the numbers $5, 20$ in which one number is the factor of the other. What do you observe in the results obtained?