What is the product of 21% and some number?

1 Answer
Sep 29, 2015

Answer:

#.21x#, where #x# is some number.

Explanation:

The first step is figuring out what 21% is as a number. Well, 21% means 21 parts out of a 100 - which can be expressed as the fraction #21/100#. We could leave it like this, but decimals are easier on the eyes than fractions. To convert #21/100# to a decimal, all we do is divide, getting #.21#.

Next, we interpret "the product of 21% and some number". What is some number? The answer is in the question! Some number is any number - a decimal, fraction, number, square root, etc, etc. To represent "some number" in math terms, we use a letter called a variable. This variable just stands for some number - it can be anything you want it to be. Usually, variables are something like #n#, #x#, and #y#. We'll use #x# because that's the most common one.

Now, what does "product" mean? Multiplication! It's that easy. So the product of 21% (#.21#) and some number (#x#) is #.21# multiplied by #x#, or #.21x#.