Q15 of 124 Page 1

A circular field has a circumference of 360 km. Three cyclists start together and can cycle 48, 60 and 72 km a day, round the field. When will they meet again?

Circumference of the circular field is 36 km


Time taken by first cyclist = = = 7.5 days ⇒ 7.5×24 = 180 Hrs


Similarly,


Time taken by second cyclist = = 6 days ⇒ 6×24 = 144 Hrs


Time taken by third cyclist = = 5 days ⇒ 5×24 = 120 Hrs


Now LCM of 180, 144 and 120 is 720


Therefore the time when all three will meet again = = 30 days


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