A green light blinks every 4 seconds, and a yellow light blinks every 5 seconds. When will both lights blink at the same time?
A red light blinks every 12 seconds, and a blue light blinks every 9 seconds. When will both lights blink at the same time?
Explain how to tell when 2 lights blink together.
Problem 2
List all multiples of 10 up to 100.
List all multiples of 15 up to 100.
What is the least common multiple of 10 and 15?
Problem 3
Cups are sold in packages of 8. Napkins are sold in packages of 12.
What is the fewest number of packages of cups and the fewest number of packages of napkins that can be purchased so there will be the same number of cups as napkins?