To calculate Chin’s new monthly net pay, we need to consider his current deductions and how they will change with the reduction in his federal income tax deduction.

Currently, Chin’s total deductions amount to $420 + $95 + $89 + $40 = $644.

To find his new federal income tax deduction, we can calculate 11% of his monthly gross income: 0.11 * $3,500 = $385.

Now, we can subtract the new federal income tax deduction from his total deductions to find his new monthly net pay:

New Monthly Net Pay = Monthly Gross Income – Total Deductions
New Monthly Net Pay = $3,500 – ($385 + $95 + $89 + $40)
New Monthly Net Pay = $3,500 – $609
New Monthly Net Pay = $2,891

Therefore, Chin’s new monthly net pay, after reducing his federal income tax deduction from 12% to 11%, would be approximately $2,891.