Please help. Apparently its not as simple as just multiplying the income to the corresponding tax table number in one step.

Using the tax table, determine the amount of taxes for the following situations: (Do not round intermediate calculations. Round your answers to 2 decimal places.) a. A head of household with taxable income of $57,000. Tax amount b. A single person with taxable income of $35,800. Tax amount c. Married taxpayers filing jointly with taxable income of $72,400. Tax amount Rate on Taxable Income 10% 12% 22% 24% 32% 35% 37% Single Taxpayers Up to $9,875 $9,876-$40,125 $40,126-$85,525 $85,526-$163,300 $163,301-$207,350 $207,351-$518,400 Over $518,401 Married Taxpayers Filing Jointly Up to $19,750 $19,751-$80,250 $80, 251-$171,050 $171,051-$326,600 $326,601-$414,700 $414,701-$622,050 Over $622,051 Heads of Household Up to $14,100 $14,101-$53,700 $53,701-$85,500 $85,501-$163,300 $163,301-$207,350 $207,351-$518,400 Over $518,401