Final answer:
Sally's estimated Federal withholding tax, given the hypothetical flat rate of 15%, would be $1,755 based on her federal taxable income of $11,700.
Step-by-step explanation:
To determine how much Federal withholding tax should be deducted from Sally's paycheck, one would normally refer to the IRS Publication 15-T for the appropriate year to find the withholding tables and methods that apply to her income and filing status. However, given the details provided in the question, we can apply hypothetical rates to estimate the deductions. Since Sally has a federal taxable income of $11,700 and is married, we will assume a flat rate of 15% for federal and state taxes as per the problem's instructions, although in practice, the rate might differ based on her actual filing status and the total number of allowances and deductions she claims.
Therefore, Sally's estimated Federal withholding tax would be:
15% of her federal taxable income of $11,700, which equals $1,755.