Scot and Vidia, married taxpayers, earn $15,000 in taxable income and $5,000 in interest from an investment in City of Tampa bonds. (Use the U.S. tax rate schedule for married filing jointly). (Do not round intermediate calculations. Round your answer to 2 decimal places.)

a. If Scot and Vidia earn an additional $5,000 of taxable income, what is their marginal tax rate on this income?

Tax rate Married filing jointly or qualifying widow

10% $0 to $18,550

15% $18,551 to $75,300

25% $75,301 to $151,900