Weird Maths for CDEF - Please help

[aaronnicoli]

Hi all,

I have a maths prob and cannot work it out.

I need this to run a CDEF, but can someone make this for f.


where i = 100; p = 30;

find for f.

i = f - (f * (p / 100))

eg.
100 = f - (f * (30 / 100))
100 = f - (f * .3) #cannot get past this :S

Thanks in advance

[aaronnicoli]

Someone else helped me work it out elsewhere:

i = f - (f * (p / 100))Multiply through by (100 / p):

i * (100 / p) = f * (100 / p) - fFactorize RHS:

i * (100 / p) = f * (100 / p - 1) = f * ((100 - p) / p)Multiply through by (p / (100 - p)):

i * 100 / (100 - p) = fIn your example:

f = 100 * 100 / (100 - 30) = 100 * 100 / 70 = 1000 / 7