Answer:
[tex]Meeting\ Time = 6:03\ pm[/tex]
Step-by-step explanation:
Given
[tex]Start\ Time= 5:45pm[/tex]
[tex]Lixin = 18\ min/round[/tex]
[tex]Khairul = 360\ seconds/round[/tex]
[tex]Devi = 4minutes/2\ rounds[/tex]
Required
Determine their next meeting time
First, we need to get their unit rate in minutes per round
[tex]Lixin = 18\ min/round[/tex]
[tex]Khairul = 360\ seconds/round[/tex]
Convert 360 seconds to minutes
[tex]Khairul = \frac{360}{60} min/round[/tex]
[tex]Khairul = 6 min/round[/tex]
[tex]Devi = 4minutes/2\ rounds[/tex]
Divide by 2/2
[tex]Devi = 2mins/round[/tex]
So, we have:
[tex]Lixin = 18\ min/round[/tex]
[tex]Khairul = 6 min/round[/tex]
[tex]Devi = 2mins/round[/tex]
Next, is to determine the LCM of 18, 6 and 2
[tex]18=2 * 3 * 3[/tex]
[tex]6 = 2 * 3[/tex]
[tex]3 = 3[/tex]
Their LCM is:
[tex]LCM = 2 * 3 * 3[/tex]
[tex]LCM = 18[/tex]
This means that they will meet 18 minutes after their initial time of departure.
So:
[tex]Meeting\ Time = 5:45\ pm + 18\ minutes[/tex]
[tex]Meeting\ Time = 6:03\ pm[/tex]