Math CentralQuandaries & Queries


Question from Keli, a student:

if the gst in ontario is 5% and the pst is 8% the total tax would be 13%. How come the total tax is 1.13? Shouldn't it be 0.13?

Hello Keli,

You are quite right! If you just want to calculate how much tax you would pay on an item you would multiply the dollar amount by 0.13; However, if you wish to calculate the total cost of an item
(price+tax) you would multiply the dollar amount by 1.13, for example:

Let's say you wanted to buy a $2 item, you would pay $(0.13)(2)= $0.26 in taxes.
But, in total, you would give the cashier $(1.13)(2)= $2.26 to pay for the item.



You ae right; perhaps the wording is confusing. The total tax [on a dollar] is $0.13, if the taxes are collected independently of each other. The total cost including tax is $1.13.

[If one tax is collected on the price including the other tax, then the final amount is $1.134 and the tax is $0.134.]

Good Hunting!

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