Question

A red light flashes once every 28 seconds and green light flashes once in every 32 seconds. If both of them flashed together at 9 a.m. When will they flash together again? Step wise step ​

Answer 1

Answer:

Red light flashes after every 28 seconds and green light flashes after every 32 seconds.

L.C.M of (28,32) = 224

So, both the lights will be flashing together in every 224 seconds = 3 minutes 44 seconds

Number of minutes in a day= 24×224=5376

So, both the lights will flash 5376 times a day.

Then they flash together around at 9 :03 am

Thanks for reading my answer. Hope this helps. Have a good day.

Answer 2

Given,

A red light flashes once every 28 seconds

A green light flashes once every 32 seconds

To Find,

When will they flash together again if they flash together at 9 a.m. =?

Solution,

A red light flashes every 28 seconds and green light flashes once every 32 seconds. Therefore,  we have to find their least common factor.

LCM(28 , 32) = 224

The red and green light will flash together after every 224 seconds.

Time  = 224 seconds

TIme = 224 / 60 minutes

Time = 3 minutes and 44 seconds

The red and green light will flash together after every 3 minutes and 44 seconds.

Hence, both lights will flash together again at 3 minutes and 44 seconds past 9 a.m.