Question

A red-light flashes every 28 seconds. A green light flashes every 24
seconds. They both flash at the same time. After how many seconds will
they both next flash at the same time

Answer 1

Answer:

168 seconds

I edited the answer.

Step-by-step explanation:

To find the the time taken for both lights to flash at the same time, we need to find the lowest common multiple of 28 and 24.

28 x 6 = 168, 24 x 7 = 168

The LCM of 28 and 24 is 168.

So it takes 168 seconds for both lights to flash at the same time.

Answer 2

Both lights will flash together again at 2 minutes and 8 seconds.

To find When will they flash together again if they flash together.

What is LCM?

LCM is the method to find the smallest possible multiple of two or more numbers.

Given that,

A red light flashes once every 28 seconds

A green light flashes once every 24 seconds

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 , 24) = 168

The red and green light will flash together after every 168 seconds.

Time  =168 seconds

Time =168 / 60 minutes

Time = 2 minutes and 8 seconds

The red and green light will flash together after every 2 minutes and 8 seconds.

Hence, both lights will flash together again at 2 minutes and 8 seconds.

Learn more about LCM here:

https://brainly.com/question/22400981

#SPJ2