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StevenC707
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Number Prop Ch1 Problem #4 given that 6 is a divisor of r

by StevenC707 Wed Feb 03, 2016 1:20 am

Hi Every one, I have a question on MGMAT Guide 5 Number Properties 6th edition Chapter 1 Problem Set Question #5 (Pg23)

It goes as following: Given that 6 is a divisor of r and r is a factor of s, is 6 a factor of s?

My immediate thought is that this is a question that tests the factor foundation rule. The factor foundation rule states that if a is a factor of b, and b is a
factor of c, then a is a factor of c. However, the question only mentions 6 as a divisor. It didn't state that 6 divides evenly into r with no remainder (and thus 6 is a factor of r). Thus, I concluded that I cannot apply the factor foundation rule, and answered "Cannot Be Determined".

However, in the answer key, it states that by the factor foundation rule, if 6 is a factor of r and r is a factor of s, then 6 is a factor of s.

Can any one give some insight on why this is the case? Any help is greatly appreciated! :D
RonPurewal
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Re: Number Prop Ch1 Problem #4 given that 6 is a divisor of r

by RonPurewal Tue Feb 09, 2016 8:14 am

"this is a divisor of that" and "this is a factor of that" are the same statement.

in other words, divisor and factor are the same thing.