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Three friends are exercising together. The first friend runs a lap in 12 minutes, the second in 18 minutes, and the third in 24 minutes. If they all s
Question

Three friends are exercising together. The first friend runs a lap in 12 minutes, the second in 18 minutes, and the third in 24 minutes. If they all start running together, after how many minutes will they all finish a lap together again?

A.

82 mins

B.

92 mins

C.

72 mins

D.

32 mins

Correct option is C

Given:

Times taken for one lap: 12 min, 18 min, 24 min

Concept Used:

The time after which they meet again is the Least Common Multiple (LCM) of 12, 18, and 24.

Solution: 

Prime factors:

12 = 2² × 3

18 = 2 × 3²

24 = 2³ × 3

LCM = 2³ × 3² = 8 × 9 = 72

They will all finish a lap together again after 72 minutes.

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