Question 1059194

I find its often best to keep the number of variables to a minimum, so let's set the first number to n then relate all the others to n, to the extent possible:
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Let n = first integer
   n+2 = 2nd
   n+4 = 3rd
   n+6 = 4th

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Two times first plus 3rd equals 16:
   2(n) + (n+4) = 16
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We just need to solve for n and we're done!
    2n + n + 4 = 16
       3n + 4 = 16
        3n = 12
        3n/3 = 12/3
              n = 4

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Ans:   The four numbers are  4, 6, 8, and 10

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Check:
         Does 2(4) + 8 = 16?   yes it does.
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