Adding percentages is a relatively easy topic, just make sure you know where the decimal point is at all times.

REMEMBER: A percentage is a just a different way to show a decimal number.

1. If the number is a decimal: moving the decimal place TWO spaces to the right and adding the % symbol, you can turn any decimal into a percentage.
2. If the number is a percentage: moving the decimal place TWO spaces to the left and deleting the % symbol, you can turn any percentage into a decimal.

For example (decimal to percentage):

.15 = 15% (moved decimal two spaces to the right and added the % symbol).

.29 = 29% (moved decimal two spaces to the right and added the % symbol).

1 = 100% (there are imaginary zeros behind numbers...so this would end up being 1.00. (moved decimal two spaces to the right and added the % symbol).

.05 = 5% (moved decimal two spaces to the right and added the % symbol).

.007 = 0.7% (note that if there is a decimal place in front of the number AFTER you have moved it two spaces to the right, then the percentage is also expressed as a decimal, but with a % symbol). (moved decimal two spaces to the right and added the % symbol).

For example (percentage to decimal):

10% = .10 (moved the decimal place TWO spaces to the left and deleted the % symbol)

100% = 1 (moved the decimal place TWO spaces to the left and deleted the % symbol)

4% = .04 (moved the decimal place TWO spaces to the left and deleted the % symbol)

The best piece of advice here is to line up the decimal points of the numbers you are adding. Perform the addition as normal and keep the decimal place the same.

For example, adding 15% and 25% we would convert to .15 and .25, add, then convert back to a percentage: (move decimal place two spaces to the right and add the % symbol).