Merry soy, married, earns a weekly salary of $830 and claims one withholding allowance. by the percentage method, how much income tax will be withheld?

You need to find the amount subject to withholding, subtracting from the weekly salary the amount for one withholding allowance for weekly salaries, which is 77.90$:

830 - 77.90 = 752.1 $.

Then, look in the Fed Tax tables (
http://www.opers.ok.gov/Websites/opers/images/pdfs/2016-Fed-Tax-Tables.pdf ) for a married person with a weekly payroll.

You previously found an amount of  752.1 which is greater than 521 but less than 1613$: therefore the income tax to withhold is 35.70$ + 15% of excess over $521.

Therefore, calculate the income tax due: 35.70 + (752.1 - 521) × 15 ÷ 100 = 70.37$

The total amount of income tax that will be withheld is 70.37$