Answer:
120 minutes
Yes my answer makes sense
Step-by-step explanation:
This question has to do with Lowest Common Multiples
1) After how many minutes will both lights change at the same time again?
Step 1
We would find and list multiples of each number until the first common multiple is found.
Multiples of 30:
30, 60, 90, 120, 150, 180
Multiples of 40:
40, 80, 120, 160, 200
Step 2
The first common multiple of 30 aand 40 is the lowest common multiple.
Therefore,
LCM(30, 40) = 120
Therefore, both lights will change at the same time after 120 minutes.
2) Why does your answer make sense?
Lowest common multiple is a methodology used in mathematics to show the relationship between two numbers based on their multiples.
My answer makes sense because the only way both traffic light would come up at the same time can only be determined using the methodology of Lowest Common Multiple.
Hence, both lights will change at the same time after 120 minutes.
