Sumaya is using two different strings of Christmas lights to decorate her house. one string flashes every 10 seconds. the other one string flashes every 15 seconds. when Sumaya turns on the lights they flashes at the same time. work out how long it will be before they flash again at the same time. use the LCM to help you work out your answer​

30 seconds

Step-by-step explanation:

From the question, we are informed that one string flashes every 10 seconds while the other one string flashes every 15 seconds.

The number of minutes that it'll take before they both flash again at the same time will be gotten by calculating the LCM of 10 and 15. This will be:

10 = 10, 20, 30, 40, 50 ...

15 = 15, 30, 45, 60, 75

We can see that the lowest common multiple of 10 and 15 is 30. Therefore, the answer is 30.

They'll both flash again at same time in 30 seconds.

step-by-step explanation:

cats

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