Usually, you want to know the percentage that one part of a whole is compared to the whole.
That tells you : If the whole ensemble would be 100 elements then this part would represent x of these.
Learning a new topic will take a few hours or days, so it will help if you could narrow down your area of difficulty. Are you needing to learn what a "percentage" is? How to convert between decimals, fractions, and percents? How to set up and solve basic "percent of" word problems? Or something else?
Please be complete. Thank you!
it is better to ask specific questions to get help. any clarification in the concepts will come to light in going through them.
any way, see post #5 here
as well as this article