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Expert: Sherry Wallin - 11/2/2009


Question
In how many zeros does 150! end?  Show your reasoning.  I am so lost by this question.

Answer
check out 5! and 10! and 15! and 20! and you will find that each multiple of 5 adds a 0 so in  150! there are 30 zeros because there are 30 fives in 150. Additionally you need to count an extra 0 for when you are multiplying by 100 because it has two zeros in it. So it is more than 30 zeros, it is 31 zeros in 150!

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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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