We need to know how much tax she must pay based on her taxable income ,
Since un the table it states that taxable incomes that range between $0-$132000have a tax rate of 18% of each $1 .
We already know her taxable income that is = 129000, which ranges between 0 and 132000.
Hence we know how much tax she must pay .
First , we need to calculate how much 18% of $1 is
= 18/100 x 1 = $0.18
Per annum/year = $0.18 x $129,000 = $23,220
Per month = $23,220 / 12 = $1,935
Hope you found this helpful , good luck !
