Question 1175834
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It is about finding the Least Common Multiple LCM  of the numbers  28 and 6.


    LCM(28,6) = 7*4*3 = 84.


<U>ANSWER</U>.  In 84 days.



To find LCM, you use prime decomposition of the two numbers, 28 and 6


    28 = 4*7 = {{{2^2*7}}},   6 = 2*3.


Then you take all participating prime numbers, 2, 3 and 7,  and raise each prime to the maximum participating degree.


Doing this way, you get factors  {{{2^2}}}, 3 and 7.


To get LCM, you multiply these factors.
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