question

 

x, y, z start at the same time in the same direction to run around a circular stadium. x completes a round in 63 seconds, y in 105 seconds and z in 210 seconds. if they start at the same time, then at what time will they meet again at the starting point?

 

 option 1)
  

 

  
 
 option 2)
  

 

  
 
 option 3)
  

 

  
 
 option 4)
  

 

  
 
 option 5)
  

 -

  
 

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