Grade 5 problem

Arithmetic · Grade 5

Two warning lights flash every 12 and 18 seconds. Now they blinked simultaneously. In how many seconds will this happen again for the first time?

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  1. Find the smallest number that is a multiple of both 12 and 18.
  2. Compare the series of multiples of 12 and 18.
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Answer: 36

We need to find the least common multiple of the numbers 12 and 18. It is 36, which means the lights will flash together again after 36 seconds.

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