4A = E , A=E/4-----(1)
B/4=E , B=4E-------(2)
C+4=E, C=E-4------(3)
D-4=E, D=E+4------(4)
Substitute all values in 5th equation,
A+B+C+D=100 = E/4 + 4E + E-4+ E+4 =100
E/4 + 6E = 100
25E = 400
E=16 ANS....
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