MATHAMATICAL EQUATION QUESTION
- Thread starter BOB.ELOD
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430 = 100%
430 - 18% = 352.6
100 % - 18% = 82%
352.6/82 = 4.3 * 100 = 430
430 - 18% = 352.6
100 % - 18% = 82%
352.6/82 = 4.3 * 100 = 430
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Smarty-pants!! 
No, bookkeeper
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What is it you're truing to work out?
If a percentage reduction has been applied (or if VAT has been added), it's obviously, as you've discovered, not simply a case of applying the percentage to the new calculated figure.
If for example you've got a price that includes VAT, but the VAT amount isn't shown, you can't just work out 17.5% of the VAT inclusive price since the 17.5% was added to a different sum.
For example, to make to make the example simple, lets assume you've got a price of £100 plus VAT. When 17.5% is added to £100, you get £117.50. However, if you then take 17.5% off £117.50, you're left with £96.94 - less than the original £100. Therefore, to work out what the VAT exclusive price is (and therefore how much the VAT is, you need to divide the VAT inclusive price by 1.175. £117.50 / 1.175 = £100.
The same goes for any percentage figure so if you're working out the VAT exclusive price of gas or leccy at 5%, you'd divide by 1.050.
Woodyoulike's example is correct although if you don't know what percentages have been applied then you need to work this out before you can do the calculation. For example, if an invoice is made out stating:
£430 less discount = £352.60p.
You want to know what percentage discount you've been given.
Divide £352.60 by the full price and multiply by 100. This tells you that £352.60 is 82% of £430 so you now know that the difference between 100% and 82% is 18% and the discount you have been given is therefore 18%.
Confused? I'm not surprised - I'm not good at explaining things.
If a percentage reduction has been applied (or if VAT has been added), it's obviously, as you've discovered, not simply a case of applying the percentage to the new calculated figure.
If for example you've got a price that includes VAT, but the VAT amount isn't shown, you can't just work out 17.5% of the VAT inclusive price since the 17.5% was added to a different sum.
For example, to make to make the example simple, lets assume you've got a price of £100 plus VAT. When 17.5% is added to £100, you get £117.50. However, if you then take 17.5% off £117.50, you're left with £96.94 - less than the original £100. Therefore, to work out what the VAT exclusive price is (and therefore how much the VAT is, you need to divide the VAT inclusive price by 1.175. £117.50 / 1.175 = £100.
The same goes for any percentage figure so if you're working out the VAT exclusive price of gas or leccy at 5%, you'd divide by 1.050.
Woodyoulike's example is correct although if you don't know what percentages have been applied then you need to work this out before you can do the calculation. For example, if an invoice is made out stating:
£430 less discount = £352.60p.
You want to know what percentage discount you've been given.
Divide £352.60 by the full price and multiply by 100. This tells you that £352.60 is 82% of £430 so you now know that the difference between 100% and 82% is 18% and the discount you have been given is therefore 18%.
Confused? I'm not surprised - I'm not good at explaining things.
You are, rest a suredFredFlintstone said:
In fact it is quite simple (as everyhting you do know is
)What is the base? That is your 100%
In your VAT example you want to know the ex VAT amount (while knowing the VAT rate). So, ex VAT = 100%, the including VAT amount = 117.5%.
Going back to the ex VAT = £117.5/117.5*100 = £100
And you explanation about the discount is spot on, concentrate on the base 100% and take it from there.
to subtract a percentage i always do as Fred says and divide by the appropriate number.
i.e. to subtract 17.5% simply divide the number by 1.175 as said earlier.
i.e. to subtract 17.5% simply divide the number by 1.175 as said earlier.
I know, I do the same, but the elaborate example was more to explain the basic principle of finding the 100% base
According to my limited knowledge of the English language you mean a bookkie.
Sorry to have to disappoint you now, I'm one of those number chrunchers I'm afraid (and they are very well known NOT to gamble)
oh you mean accountant (turf)WoodYouLike said:
According to my limited knowledge of the English language you mean a bookkie.
Sorry to have to disappoint you now, I'm one of those number chrunchers I'm afraid (and they are very well known NOT to gamble)
I wish (would make much more money then)tim west said:oh you mean accountant (turf)WoodYouLike said:
According to my limited knowledge of the English language you mean a bookkie.
Sorry to have to disappoint you now, I'm one of those number chrunchers I'm afraid (and they are very well known NOT to gamble)
No, I prepare our books for our excellent accountant (and pay less because of that) = book keeper
If your 'discount is 18%, and 568 is the end amount your paying, then yes.BOB.ELOD said:
The original amount would be 693
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