Cash related fixed costs = Total fixed costs - Depreciation
Substituting for the given values;
Cash related fixed costs = 450,000 - (5/100*450,000) = 450,000 - 22,500 = $427,500
Now;
Cash break-even point = Cash related fixed costs/Contribution margin
Therefore;
Cash break-even point = 427,500/4.10 = 104,268.29 ≈ 104,269 units