Question 1089278:  Find the least 5- digit number which is exactly divisible by 20 ,  25 ,  30. 
 
 Answer by Theo(13342)      (Show Source): 
You can  put this solution on YOUR website! the least common multiple of 20, 25, and 30, is 300. 
i believe that any larger numbers that are multiples 20, 25, and 30 have to be multiples of 300. 
10,000 / 300 = 33.333 
33 * 300 = 9900 
34 * 300 = 10200 
that looks like the smallest 5 digit number that's divisible by 20, 25, 30 is 10200. 
i tested this out with a program that i wrote in excel and it tells me that my assumption is correct and that 10200 is the least 5 digit number that is a common multiple of 20, 25, and 30. 
the least 5 digit number has to be a number greater than or equal to 10000. 
the next smaller number is 9999 which is a 4 digit number.
 
 
 
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