How do you know what the corporate tax rate is?

How do I get a subtotal if I only have the final total but know the tax rate?

• Hi, I will give a simple example. The subtotal is $100 first multiplied by .10 and that amount is added to the subtotal $100 + $10 = $110. That $110 is then multiplied by .05, which is $5.50 and then added This makes the grand total $115.50 Now, if I only have the $115.50, how do I figure out the amounts for the seperate taxes? Not great at max and been exhausting my brain over this. Please help

• Answer:

  You have the second tax compounding on the first. Is that really how they do it where your are? Charging tax on tax? Wow. If you have the total only, and the taxes are tax 1 and tax 2, r and q, then the thing could be expressed as Total with all taxes = T tax 1 = r tax 2 = q total before tax = t T = t(1+r) * q + t(1+r) T = t(1+r) * (q + 1) Divide both sides by t, which gives T/t = (1+r) * (q + 1) Then divide both sides by T 1/t = (1+r) * (q + 1) / T At which point you can substitute in your tax rates and solve for t. A bit messy, but it will work. If you don't actually have the second tax compounding on the first, the math is much easier. To get the tax amounts from the total with tax tax 1 amount = T*r/(1+r+q) In Ontario we had pst 8% and gst 5%. GST only from total was total times 5/113, pst only was total times 8/113. Now we have hst 13%; hst only from total = total times 13/113. When you have the tax only amounts, subtract them from the total to get the sub total before tax.