Math me on percentages

nazali · 10-02-2022, 05:36 PM

OK,
I thought this was simple but this is probably the day I skipped school

I'm basically trying to double check my figures, I have a spreadsheet showing
gross, taxes etc, now as a checksum, I wanna double check some figures in reverse.

I have a big amount I wanna double check and somehow I can't get the math to work out, my formula is wrong !

example:

I charged for a service 13% (on the invoice) on my spreadsheet I dont show the Net, just the gross (inc Tax) I have a column for the tax part

$1440 + 13% = $187.20 = $1627.20

So now I wanna check the end figure the $1627.20 (did I charge the right amount of tax or did I typo somewhere) (so this is a years worth of invoices.)

So I thought OK easy peasey, take off 13% of the total and bingo

but $1627.20 / 100 * 13 = $211.53 oh oh not $187.20

I tried google but I'm coming up stuck, sorry I feel really stupid asking this !

Maybe I need to redo the colum from my invoices and do a Net column instead of a gross column, then the tax colum

Patrick303 · 10-02-2022, 05:44 PM

Quote:

Originally Posted by nazali

but $1627.20 / 100 * 13 = $211.53 oh oh not $187.20

That's because here you're figuring out 13% of $1627.20 and not the original $1440

________ · 10-02-2022, 05:50 PM

Total / 1.13 (1+13% = 1+0.13)

1627.20 / 1.13 = 1440

ASAP · 10-02-2022, 08:51 PM

First try was right... you are going off a higher base in the 2nd...

nazali · 10-02-2022, 09:31 PM

ahh awesome guy's txs, I felt so stupid, txs can see where I was going wrong
many thanks again !

Tommy-G · 10-03-2022, 07:22 AM

Quote:

Originally Posted by nazali

ahh awesome guy's txs, I felt so stupid, txs can see where I was going wrong
many thanks again !

Sometimes you look at a problem so long you become blinded by it

nazali · 10-03-2022, 09:34 AM

I knew I was using the wrong calculation but couldn't figure it out and trying to google it was driving me nuts

Quote:

Originally Posted by Tommy-G

Sometimes you look at a problem so long you become blinded by it

10-02-2022, 05:36 PM	#1
nazali Major 1298 Rep 1,146 Posts Drives: 230 2020 vert F23 Join Date: Jun 2020 Location: Total Wack Job iTrader: (0)	Math me on percentages OK, I thought this was simple but this is probably the day I skipped school I'm basically trying to double check my figures, I have a spreadsheet showing gross, taxes etc, now as a checksum, I wanna double check some figures in reverse. I have a big amount I wanna double check and somehow I can't get the math to work out, my formula is wrong ! example: I charged for a service 13% (on the invoice) on my spreadsheet I dont show the Net, just the gross (inc Tax) I have a column for the tax part $1440 + 13% = $187.20 = $1627.20 So now I wanna check the end figure the $1627.20 (did I charge the right amount of tax or did I typo somewhere) (so this is a years worth of invoices.) So I thought OK easy peasey, take off 13% of the total and bingo but $1627.20 / 100 * 13 = $211.53 oh oh not $187.20 I tried google but I'm coming up stuck, sorry I feel really stupid asking this ! Maybe I need to redo the colum from my invoices and do a Net column instead of a gross column, then the tax colum
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10-02-2022, 05:50 PM	#3
________ ________ 4159 Rep 2,301 Posts Drives: ________ Join Date: Sep 2018 Location: ________ iTrader: (0)	Total / 1.13 (1+13% = 1+0.13) 1627.20 / 1.13 = 1440
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10-02-2022, 08:51 PM	#4
ASAP Major General 10137 Rep 8,612 Posts Drives: '23 X3 M40i Join Date: Sep 2012 Location: FL iTrader: (0)	First try was right... you are going off a higher base in the 2nd... __________________ 2 x N54 -> 1 x N55 -> 1 x S55-> 1 x B58
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10-02-2022, 09:31 PM	#5
nazali Major 1298 Rep 1,146 Posts Drives: 230 2020 vert F23 Join Date: Jun 2020 Location: Total Wack Job iTrader: (0)	ahh awesome guy's txs, I felt so stupid, txs can see where I was going wrong many thanks again !
	Appreciate 0 Quote