hi, I've been playing with an if function i just cant figure out for about close to an hour, i figure it will be much faster just asking someone experienced.

I have three columns. A, B, C lets say

Each have many rows of data in them

the function im trying to do is, "if the Sum of Column A is between 25 and 35% of the sum of columns A, B and C make the cell Green, if not, make it red?

another easier question that i need is "If sum of column D is between 470 and 530 make cell green color, if not, make red"

if the color thing is too hard to do, ill just make it say true false or whatever, just would be more aesthically pleasing if it was red or green. The main thing is the formula

thanks in advance