How can you use ' factorization to determine if 856 is evenly divisible by 7?

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How can you use &#039; factorization to determine if 856 is evenly divisible by 7?

Ueberbachge · Accepted Answer

Step 1                    856                                      /                ∖                            2                 428                                      /                ∖                            2                 214                                      /                ∖                            2                 107            If we knew that 107 is &#039; then we would be done.It is not divisible by 2 since the last digit is not even.It is not divisible by 3 since the sum of the digits       1    +    0    +    7    =    8   is not divisible by 3It is not divisible by 5 since the last digit is neither 5 nor 0.The next factor to try would be 7, which is the one we&#039;re wanting to test anyway.I&#039;m not sure this factorisation has helped us much, but let us at least split it down to make the arithmetic a little easier:            107      7        =                  70        +        35        +        2            7        =          70      7        +          35      7        +          2      7        =    10    +    5    +          2      7        =    15          2      7      So 107 is not divisible by 7 and neither is 856.

How can you use ' factorization to determine if 856

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