a + b + c + d = 1000
a - x = 49 => a = 49 + x
b - x = 87 => b = 87 + x
c - x = 34 => c = 34 + x
d - x = 30 => d = 30 + x
49 + 87 + 34 + 30 + 4x = 1000
200 + 4x = 1000
4 ( 50 + x ) = 1000 | /4
50 + x = 250 => x = 250 - 50
=> x = 200
a = 49 + 200 = 249
b = 87 + 200 = 287
c = 34 + 200 = 234
d = 30 + 200 = 230
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