Question 1158265
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Let "n" be the unknown number under the question.


Add 1 (one) to the number, and consider N = n+1, instead of "n".


Then the number N  is a multiple of 4 (OBVIOUS).

Also, the number N is a multiple of 5 (OBVIOUS).


The only numbers lesser than or equal to 40 and multiple to 4 and 5 are the numbers 20 and 40.


Returning from "N" to "n", we have, therefore, two answers for the given problem:  19 and 39.
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Solved.


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For similar solved problems, &nbsp;see the lesson

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/divisibility/lessons/The-number-that-leaves-a-remainder-1-when-divided-by-2-by-3-by-4-by-5-and-so-on-until-9.lesson>The number that leaves a remainder 1 when divided by 2, by 3, by 4, by 5 and so on until 9</A>

in this site.