Advanced Math/arithmetic

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Expert: Sherry Wallin - 3/11/2009


Question
how can i find the lcm of 3 20 and 15 i have been stuck on this for about 20 min now

Answer
lindzye~
    There are lots of methods but probably the easiset is to multiply each by 1, then 2, then 3, up to about 5 and then the first time a number shows up in all 3 lists the smallest when it occurs will be the lcm 'least common multiple'.

Example lcm 5,12,20
5,10,15,20,25,30,35,40,45,50,55,60
12,24,36,48,60
20,40,60

60 is the lcm of 5,12,20

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Sherry Wallin

Expertise

I can answer most questions up through Calculus and some in Number Theory and Abstract Algebra.

Experience

I have had my Bachelor's Degree since 1987 and have been a teacher since 1988. I earned my Masters Degree in Mathematics May 2010. I have been teaching at the same community college since 2002.

Education/Credentials
I have taught 12 years at the community college level, medical college, and technical college as well as a high school instructor and alternative education instructor and charter school instructor.

Awards and Honors
Master's GPA 3.56 Bachelor's GPA 3.34 Post grad work not degree related GPA 4.0

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