Posted by **Anonymous** on Monday, July 8, 2013 at 7:07am.

the green light flashes every 3 seconds,the red every 5 seconds and white at 10 seconds. iF they flash at 12 noon.When will they flash together again in a minute? in an hour?

- Math -
**MathMate**, Monday, July 8, 2013 at 7:55am
Both, in a minute and in an hour.

The LCM of 3, 5 and 10 is the same as the LCM of 3 and 10 because 5 divides 10 (5 is a factor of 10).

The LCM of 3 and 10 is 30.

So the soonest the will flash together is 30 seconds.

## Answer this Question

## Related Questions

- tech III math ( ACT Prep) - A neon sign flashes every 4 seconds, another neon ...
- Math - Three lighthouses on three nearby islands flash their lights every ...
- maths - a light house flashes every 56 seconds. Another lighthouse flashes every...
- math - a red light winks every 6 seconds, a white one every 10 seconds, and a ...
- MATH - One light flashes every 2 minutes and another light flashes every 3.5 ...
- MATH - One light flashes every 2 minutes and another light flashes every 3.5 ...
- Mathh :/ - A light flashes every 15 minutes. a second light flashes every 18 ...
- general ability - light X flashes every 3 minutes. Light Y flashes every 5 ...
- math, 5th grade - I am really stuck on how to figure this answer out, could you...
- Math - A bell rings every 2 seconds, and a bird chirps every 3 seconds. If the ...