Lesson 6.126.12 Small Group · Group 1
Group 1 · Set BSecond form · new problems, same idea
Learning target With my small group, I can find the least common multiple (LCM) of two numbers by listing or comparing their multiples — one step at a time, with support.
Remember6.12 Small Group · Group 1
To find the LCM, list the multiples of each number and pick the smallest number that is in both lists. The least common multiple (LCM) of two numbers is the smallest number that is a multiple of both.
Words: Least Common Multiple (Mínimo común múltiplo)Multiple (Múltiplo)Common multiple (Múltiplo común)Skip counting (Conteo salteado)Prime factorization (Factorización prima)
-
1Complete each step, then write the final answer.
Find the LCM of 6 and 10.
Show your workHint Skip count by 10: 10, 20, 30. Find the first one that is also a multiple of 6.
Final answer: -
2Complete each step, then write the final answer.
Find the LCM of 5 and 6.
Show your workHint Skip count by 6. Find the first one that is also a multiple of 5.
Final answer: -
3Complete each step, then write the final answer.
A red light blinks every 4 seconds. A blue light blinks every 5 seconds. They blink together now. In how many seconds will they blink together again?
Show your workHint They blink together at a multiple of 4 and of 5. Find the least one.
Final answer: -
4Complete each step, then write the final answer.
Find the LCM of 2, 3 and 4. It must be a multiple of all three numbers.
Show your workHint Skip count by the largest number, 4. Test each one for 2 and for 3.
Final answer:
Explain your thinkingJay used 6 × 9 to find the LCM. Why is the product not always the LCM? Use the lists to explain.
Sentence starter The LCM is ___ because it is the first number in ___. · The product ___ is a common multiple, but ___.