Calculate number based on percentage:My algebra days

Hello -
My algebra days seem to be a little hazy today. Could someone please
assist on the basic calculation to find the original number.

example 1:
This years sales are $3700, a decrease of 11.6%. What would last years
sales be?

example 2:
This years sales are $4500, an increase of 151%. What would last years
sales be?

Thanks for any insight on this calculation.
Dan

Dan, answers to your examples are as under:

1. This years sales are $3700, a decrease of 11.6%. Last years
sales would be $4185.52.

Formula : =3700/(100%-11.60%)

2.This years sales are $4500, an increase of 151%. Last years
sales would be $2980.13

Formula : 4500/151%

Thanks,

Manish Bajpai




"[email protected]" wrote:

> Hello -
> My algebra days seem to be a little hazy today. Could someone please
> assist on the basic calculation to find the original number.
>
> example 1:
> This years sales are $3700, a decrease of 11.6%. What would last years
> sales be?
>
> example 2:
> This years sales are $4500, an increase of 151%. What would last years
> sales be?
>
> Thanks for any insight on this calculation.
> Dan
>
>

3700 = x * (1-.116), x=$4185.52
4500 = x * (1+1.51), x=$1792.83

--
David Billigmeier


"[email protected]" wrote:

> Hello -
> My algebra days seem to be a little hazy today. Could someone please
> assist on the basic calculation to find the original number.
>
> example 1:
> This years sales are $3700, a decrease of 11.6%. What would last years
> sales be?
>
> example 2:
> This years sales are $4500, an increase of 151%. What would last years
> sales be?
>
> Thanks for any insight on this calculation.
> Dan
>
>

Thanks, this is great!

Formula : =3700/(100%-11.60%)
Formula : 4500/151%

Is there one general formula to use for both scenerios, so I wouldn't
have to differentiate between positive and negative changes?

The answer for #2 is wrong, you forgot to add a 1 to the 151%. The formula is:
4500/2.51


--
David Billigmeier


"Manish Bajpai" wrote:

> Dan, answers to your examples are as under:
>
> 1. This years sales are $3700, a decrease of 11.6%. Last years
> sales would be $4185.52.
>
> Formula : =3700/(100%-11.60%)
>
> 2.This years sales are $4500, an increase of 151%. Last years
> sales would be $2980.13
>
> Formula : 4500/151%
>
> Thanks,
>
> Manish Bajpai
>
>
>
>
> "[email protected]" wrote:
>
> > Hello -
> > My algebra days seem to be a little hazy today. Could someone please
> > assist on the basic calculation to find the original number.
> >
> > example 1:
> > This years sales are $3700, a decrease of 11.6%. What would last years
> > sales be?
> >
> > example 2:
> > This years sales are $4500, an increase of 151%. What would last years
> > sales be?
> >
> > Thanks for any insight on this calculation.
> > Dan
> >
> >

Ya, in your case you can use the formula:

<Current Year Sales> = <Last Years Sales> * (1+<percentage change>)

With variables located within <>. Just solve for any variable you are
trying to find given you know the other 2. Note that if you have a decrease
in percentage you use a negative number for <percentage change>

--
David Billigmeier


"Dan" wrote:

> Thanks, this is great!
>
> Formula : =3700/(100%-11.60%)
> Formula : 4500/151%
>
> Is there one general formula to use for both scenerios, so I wouldn't
> have to differentiate between positive and negative changes?
>
>

David,

Dan's response proves that I was right in dividing 4500/151%. Dan was
looking for 151% increase and not 251% increase.

Dan,

It is my pleasure.

Why do you worry for future, when we guys are here to help you out.

Manish Bajpai

"David Billigmeier" wrote:

> The answer for #2 is wrong, you forgot to add a 1 to the 151%. The formula is:
> 4500/2.51
>
>
> --
> David Billigmeier
>
>
> "Manish Bajpai" wrote:
>
> > Dan, answers to your examples are as under:
> >
> > 1. This years sales are $3700, a decrease of 11.6%. Last years
> > sales would be $4185.52.
> >
> > Formula : =3700/(100%-11.60%)
> >
> > 2.This years sales are $4500, an increase of 151%. Last years
> > sales would be $2980.13
> >
> > Formula : 4500/151%
> >
> > Thanks,
> >
> > Manish Bajpai
> >
> >
> >
> >
> > "[email protected]" wrote:
> >
> > > Hello -
> > > My algebra days seem to be a little hazy today. Could someone please
> > > assist on the basic calculation to find the original number.
> > >
> > > example 1:
> > > This years sales are $3700, a decrease of 11.6%. What would last years
> > > sales be?
> > >
> > > example 2:
> > > This years sales are $4500, an increase of 151%. What would last years
> > > sales be?
> > >
> > > Thanks for any insight on this calculation.
> > > Dan
> > >
> > >

Manish:
151% increase DOES NOT mean multiplying a number by 1.51, it means
multiplying by 2.51. Check it for yourself:

Take a simple example: 150% increase from 2 means doubling 2 one time and
then adding another 50%... obtaining 2+2+1=5. My answer would provide the
right answer, or 2*(150%+1)=2*(1.5+1)=2*2.5=5. Your answer would only yield
3.

Look at the formula you gave for #1, 3700/(100%-11.60%). You have to do the
same thing for increases... you only had 4500/151%, you need
4500/(100%+151%)=4500/(2.51)


--
David Billigmeier


"Manish Bajpai" wrote:

> David,
>
> Dan's response proves that I was right in dividing 4500/151%. Dan was
> looking for 151% increase and not 251% increase.
>
> Dan,
>
> It is my pleasure.
>
> Why do you worry for future, when we guys are here to help you out.
>
> Manish Bajpai
>
> "David Billigmeier" wrote:
>
> > The answer for #2 is wrong, you forgot to add a 1 to the 151%. The formula is:
> > 4500/2.51
> >
> >
> > --
> > David Billigmeier
> >
> >
> > "Manish Bajpai" wrote:
> >
> > > Dan, answers to your examples are as under:
> > >
> > > 1. This years sales are $3700, a decrease of 11.6%. Last years
> > > sales would be $4185.52.
> > >
> > > Formula : =3700/(100%-11.60%)
> > >
> > > 2.This years sales are $4500, an increase of 151%. Last years
> > > sales would be $2980.13
> > >
> > > Formula : 4500/151%
> > >
> > > Thanks,
> > >
> > > Manish Bajpai
> > >
> > >
> > >
> > >
> > > "[email protected]" wrote:
> > >
> > > > Hello -
> > > > My algebra days seem to be a little hazy today. Could someone please
> > > > assist on the basic calculation to find the original number.
> > > >
> > > > example 1:
> > > > This years sales are $3700, a decrease of 11.6%. What would last years
> > > > sales be?
> > > >
> > > > example 2:
> > > > This years sales are $4500, an increase of 151%. What would last years
> > > > sales be?
> > > >
> > > > Thanks for any insight on this calculation.
> > > > Dan
> > > >
> > > >

Hmm, this "general" formula doesn't seem to work for the negative
changes. Any other thoughts?

Dan -
It actually will work, just use like so:

<Current Year Sales> = <Last Years Sales> * (1+<percentage change>)

So in your example, you had current year sales of 3700 and a decrease of
11.6%, so the formula would become (remember I said use a negative percentage
for decreases):
3700 = <Last Years Sales> * (1+(-.116))
3700 = <Last Years Sales> * (1-.116)
3700 = <Last Years Sales> * .884
Last Years Sales = 3700/.884
Last Years Sales = 4185.52

If you are getting confused by Manish (when he says an increase in sales by
151% means multiplying by 1.51), he is wrong... look:

Once again use your information:

4500 = <Last Years Sales> * (1 + 1.51)
4500 = <Last Years Sales> * 2.51
Last Years Sales = 4500/2.51
Last Years Sales = 1792.83.

Hope this helps,
--
David Billigmeier


"Dan" wrote:

> Hmm, this "general" formula doesn't seem to work for the negative
> changes. Any other thoughts?
>
>

Great...got it now! Thanks!! :o)

Dan,

No point in memoraizing a formula.

Simply understand the logic and you will never miss it:

If last year's sales = X,

Rate of increase or decrease = r%, and

This Year's revenue = 1000.

Then, 1000=X*(100%+r%) ===> note if r is to be mentioned with its symbol
i.e.ngeative for a decrease and positive for increase.

Therefore,

X = 1000/(100% + r%)

Please make sure while arrivng at r% that whether your this year's revenue
is grown by 51% over last year or grown by 151% over last year. If it ilater
case i.e. grown by 151% over last year then David is right.

Thanks,

Manish Bajpai

"David Billigmeier" wrote:

> Dan -
> It actually will work, just use like so:
>
> <Current Year Sales> = <Last Years Sales> * (1+<percentage change>)
>
> So in your example, you had current year sales of 3700 and a decrease of
> 11.6%, so the formula would become (remember I said use a negative percentage
> for decreases):
> 3700 = <Last Years Sales> * (1+(-.116))
> 3700 = <Last Years Sales> * (1-.116)
> 3700 = <Last Years Sales> * .884
> Last Years Sales = 3700/.884
> Last Years Sales = 4185.52
>
> If you are getting confused by Manish (when he says an increase in sales by
> 151% means multiplying by 1.51), he is wrong... look:
>
> Once again use your information:
>
> 4500 = <Last Years Sales> * (1 + 1.51)
> 4500 = <Last Years Sales> * 2.51
> Last Years Sales = 4500/2.51
> Last Years Sales = 1792.83.
>
> Hope this helps,
> --
> David Billigmeier
>
>
> "Dan" wrote:
>
> > Hmm, this "general" formula doesn't seem to work for the negative
> > changes. Any other thoughts?
> >
> >

does anyone know how to edit the algorythms?