567+(x78-b57)

Assuming x78 and b57 are the 3-digit numbers with hundreds digits x and b (i.e., x78 = 100x + 78 and b57 = 100b + 57):

• 567 + (x78 - b57) = 567 + (100x + 78 - 100b - 57)
• = 567 + 100x - 100b + 21
• = 588 + 100(x - b)

So the expression simplifies to 588 + 100(x - b).

If x and b are digits (0–9), then x - b ∈ [-9, 9], giving possible values: -312, -212, -112, -12, 88, 188, 288, 388, 488, 588, 688, 788, 888, 988, 1088, 1188, 1288, 1388, 1488.