Income tax In a given year, the U.S. federal income tax owed by a married couple filing jointly can be found from the following table (Source: internal Revenue Service, From
1040
Instruction).
Married Filling jointly
Taxable income
Tax Rate
$0-$18,550
10%
$18,551-$75,300
$1,855 plus 15% of the amount over $18,550
$75,301-$151,900
$10,367
.50 plus 28% of the amount over $75,300
$151,901-$231,450
$29,517
.50 plus 28% of the amount over $151,900
$231,451-$413,350
$151,791
.50 plus 33% of the amount over $231,450
$413,351-$466,950
$111,818
.50 plus 35% of the amount over $413,450
$466,951ormore
$130,578
.50 plus39
.6% of the amount over $466,950
For incomes up to
$
151
,
900
, write the pricewise defined function
T
with input
x
that models the federal tax dollars due as a function of
x
, the taxable income dollars earned.
Use the function to find
T
(
70
,
000
)
.
Find the tax due on a taxable income of
$
100
,
000
.
A friend tells Jack Waddell not to earn any money over
$
75
,
300
because it will raise his tax rate to
25
%
on all of his taxable income. Test this statement by finding the tax due on
$
75
,
300
and
$
75
,
300
+
$
1
. What do you conclude?