Question 1083090
a  > b > c > d ,  so a is the greatest of the four.
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One way to visualize:
Say a+1 = N,  then N = b+2 = c+3 = d+4

You only need to add 1 to a to get to N
You must add 2 to b to get to N
c requires 3 be added to it to reach N
d requires 4 be added to it to reach N

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 The more mathematical, and a bit more mechanical, approach:

   a+1 = b+2 = c+3 = d+4   —>  a = b+1 = c+2 = d+3    ( —> a>b )
   b+1 = c+2 = d+3 —>  b = c+1 = d+2    (—> b>c)
   c+1 = d+2  —> c=d+1      (—> c>d)

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