Question 1100922
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Shortest side + Middle side    + Longest side = 2400.

S             + M              + L            = 2400

S             + ((2S-20)-200)  + (2S-20)      = 2400.


S + 2S - 220 + 2S -20  = 2400

5S = 2400 + 220 + 20  = 2660  ====>  S = {{{2640/5}}} = 528.


<U>Answer</U>.  Shortest = 528.  Longest = 2*S-20 = 2*528-20 = 1036.  Middle = 1036-200 =  836.


<U>Check</U>.   528 + 836 + 1036 = 2400.   ! Correct !
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