quick Maths question (precentage)

kenny1999 · **Joined:** Dec 10, 2013 **Posts:** 106

Sorry a quick one

when 400 is reduced to 375
what is the percentage reduced?

Is it (400-375)/400 x 100%

or (400-375)/375 x 100%

Odinbc · **Posted:** Sat May 07, 2016 2:18 am **(#2)**

kenny1999 wrote:

Sorry a quick one

when 400 is reduced to 375
what is the percentage reduced?

Is it (400-375)/400 x 100%

or (400-375)/375 x 100%

400 - 375 = 25
(400 + 375) / 2 = 387.5
25 / 387.5 * 100 = 6.4516%

[Edit]
Percentage Difference, Error, Change

paynekj · **Posted:** Sat May 07, 2016 2:52 am **(#3)**

I'm going to disagree with Odinbc

You're trying to express a percentage of the original image, which is 400

(400-375)/400 x 100 = 6.25%

Kevin

rich2005 · **Joined:** Mar 04, 2011 **Posts:** 2604

Kevin beat me to it.

Surely the reference point for the calulation should be the value of the original size.
but...why not let Gimp do the arithmetic for you.

Attachment:

resize.jpg [ 67.27 KiB | Viewed 2237 times ]

Starting with a 400x400 pix canvas, scale down to 375x375 pix then change the units to percentage.
93.75% or 6.25% decrease

Of course, go the other way 375 -> 400 and you get a different answer. 106.67% an increase of 6.6666666%

Attachment:

resizeup.jpg [ 29.14 KiB | Viewed 2237 times ]