I wrote a conditional statement in Python which increases a price depending on the corresponding state's tax rate at the time.
In the example below, I set the purchase_amount to $17 and the state to CA. The tax rate is 7.5%. Here's is how I formulated it to get the correct answer of $18.275.
state = "CA"
purchase_amount = 17
if state == "CA":
tax_amount = .075
elif state == "MN":
tax_amount = .095
elif state == "NY":
tax_amount = .085
total_cost = tax_amount * purchase_amount + purchase_amount
However, I saw someone use a different formulation, as seen below, to get the same exact answer.
if state == "CA":
tax_amount = .075
total_cost = purchase_amount*(1+tax_amount)
I have never seen a percentage applied this way before.
My MAIN QUESTION is...Where did the integer 1 even come from??
My second question is... Why was it added to the tax_amount before multiplying it by the purchase_amount?
This was especially alarming because while it is nice to have concluded with the same correct answer regardless, I aspire to adequately read the coding styles of others.
Thank you so much for your help!
Are you asking how to factor, like algebra 2 factoring. This would be called the distribution rule, the following lines are the same, by factoring out the common factor.
tax_amount * purchase_amount + purchase_amount
purchase_amount * ( tax_amount + 1 )