2 10 points How does an employer know how much to withhold from a your paycheck for federal income tax? Your employer withholds 27% of your gross pay per IRS Guideline WH-27. O You inform you employer how much you paid in taxes last year, then your employer divides that amount by this amount is then withheld. -- You complete and submit to your employer IRS Form W-4. Employers don't withhold federal income tax from paychecks -- this is a trick