I need help with Marginal tax rate and average tax rate

Question

whpalmer4 · Answer

average tax rate is total tax paid divided by total taxable income.

marginal tax rate is the rate at which an additional unit of taxable income would be taxed

venomblast · Answer

Yea but look at this. it giving me a percentage.

whpalmer4 · Answer

Well, no one promised that you wouldn't have to do any work to answer the problem!

If the family makes $25,000, you calculate the tax on their income up to $20,000, then add that to the tax on their income from $20,001 to $25,000.  $0-$20,000 pays a rate of 0%, so that amount is $0.  $20,001 to $25,000 pays a rate of 31%, so ($25,000-$20000) *31% = $5000*31% = $1550.  Average tax rate is $1550/$25000.  Marginal tax rate is 31%.

venomblast · Answer

i am so confused. why did you subtract?

venomblast · Answer

where did you get the 20000?

venomblast · Answer

so for the 2nd question, Lee family, (123000 - by what?) *.5. what do i subtract by?