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where s is the subtotal. So s = $10 / 1.075. Since 0.075s is the PST you paid, that
As well,
where c is the cost of the goods before any taxes. So c = s / 1.06. Since 0.06c is the GST you paid, this means:
To summarize in general, if the final price is f and this includes GST and PST in Quebec:
Hope this helps, Derek wrote back:
Hi Derek. In that case, PST is calculated the same way, but the factor for the GST calculation is
Do you see how that is done?
Hi Pierre, In the line Stephen wrote $10 = s + 0.075s = s + 0.075 s think of s as 1 s and then the line becomes $10 = 1 s + 0.075 s At this point you can see s as a common factor so the expression can be written $10 = 1 s + 0.075 s = (1 + 0.075) s = 1.075s I hope this helps,  


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