Online Course Discussion Forum

Math Challenge I-A Spring 2019 Week 5

 
 
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Math Challenge I-A Spring 2019 Week 5
by Amy T - Saturday, 30 March 2019, 6:39 PM
 

find the smallest positive integer consisting entirely of 11's and 77's, at least one of each, that is divisible by 55 and 99.


but numbers that is divisible by 5 have to end in 0 or 5, and 1 and 7 wouldn't work 

 
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Re: Math Challenge I-A Spring 2019 Week 5
by David Reynoso - Monday, 1 April 2019, 10:36 AM
 

You are correct, Amy! It is not possible to have such a number.