Answer:
$13,000
Step-by-step explanation:
Standard deduction for Married filling jointly = 24,000
Adjusted gross income = $40,000
Greater of itemized deduction ($13,050) and Standard deduction ($24,000) = $27,000
Taxable income = Adjusted gross income - The greater of the 2 above
Taxable income = $40,000 - $27,000
Taxable income = $13,000
So therefore, their taxable income for 2017 is $13,000