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4 votes
Light A flashes every 8 seconds

Light B flashes every 20 seconds
Both lights flash at the same time
Work out how long it will take for both lights to flash at the same time again

User KedarX
by
8.0k points

2 Answers

3 votes

Answer:40sec

Step-by-step explanation:you get the lcm of the seconds

2 8 20

2 4 10

2 2 5

5 1 5

1 1

2×2×2×5×1=40sec

User DaveGreen
by
9.1k points
3 votes
8x5=40
20x2=40


They will both flash at the same time at 40 seconds !
User Hetepeperfan
by
8.8k points