Find the value before the increase or discount
is after aincreased, original was?
This is the reverse calculation: you know the final figure and the percentage applied, and you want the starting value. Useful for checking whether an advertised discount is genuine, and for separating a base amount out of an already adjusted price.
Original value = final value ÷ (1 ± percentage ÷ 100)
Example: an item advertised at $175 with 30% off was 175 ÷ 0.70 = $250 before the sale.
If 175 is the result after a 30% decrease, we work backwards. The final value is 0.7 times the original, so we divide to find the original.
Divide the final price by what remained after the discount. With 30% off, divide by 0.70: $175 ÷ 0.70 = $250.
Because the percentage was taken from the original value, not the final one. Adding 30% to $175 gives $227.50, not the correct $250.
Yes, as long as the tax was applied as a percentage of the base value. Enter the total paid and the tax rate to get the amount before tax.