My daughter is using a factor tree and is coming up with the wrong answer.
The three numbers are (5) (6) (15)..... I am finding the lcm as 30 through birthday cake formula. she is coming up with 450 through factor tree... which one is right and how do I show her to fix it?

Question

My daughter is using a factor tree and is coming up with the wrong answer. 
The three numbers are (5) (6) (15)..... I am finding the lcm as 30 through birthday cake formula. she is coming up with 450 through factor tree... which one is right and how do I show her to fix it?

anonymous · Answer

Multiples:

5: 10,15,20,25,30,35

6: 12,18,24,30,36

15: 30,45,60

LCM: 30

You are correct.

anonymous · Answer

Thank you so much rob_t.... but I need to know how to show her she is wrong

anonymous · Answer

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