Helpful website for "Percent of" word problems.

I was having some trouble with percent problems earlier and this website really helped me. A few of the examples that helped were:

• What percent of 20 is 30?

We have the original number (20) and the comparative number (30). The unknown in this problem is the rate or percentage. Since the statement is "(thirty) is (some percentage) of (twenty)", then the variable stands for the percentage, and the equation is:

30 = (x)(20)

30 ÷ 20 = x = 1.5

And:

If you need to find 16% of 1400, you first convert the percentage "16%" to its decimal form; namely, the number "0.16". (When you are doing actual math, you need to use actual numbers. Always convert the percentages to decimals!) Then, since "sixteen percent OF fourteen hundred" tells you to multiply the 0.16 and the 1400, you get: (0.16)(1400) = 224. This says that 224 is sixteen percent of 1400.

And:

• What is 35% of 80?

Here we have the rate (35%) and the original number (80); the unknown is the comparative number which constitutes 35% of 80. Since the exercise statement is "(some number) is (thirty-five percent) of (eighty)", then the variable stands for a number and the equation is:

x = (0.35)(80)

x = 28

Twenty-eight is 35% of 80.

Here's the link: http://www.purplemath.com/modules/percntof.htm