A flashing bulb on a string of holiday lights flashes once every $10$ seconds. Another bulb flashes once every $15$ seconds. If they are flashing together now, how long will it take for the two bulbs to flash together next again?

John and Andrew are running along a circular track. They take $48$ seconds and $56$ seconds to complete a lap, respectively. They begin from the same starting point at the same time and run in the same direction.

How long will it take for them to meet again at the starting point?

John and Andrew are running along a circular track. They take $48$ seconds and $56$ seconds to complete a lap, respectively. They begin from the same starting point at the same time and run in the same direction.How long will it take for them to meet again at the starting point?

How many laps had each boy run by then ?