If you sit in a shopping mall long enough, it is almost a certainty that you will hear someone say, "What is 25% of $60 or what is 40% of $30?"

The first step in calculating the percent of numbers is to change the percent to a decimal. When you see the word "of" in word problems, that signals multiplication, so take the decimal and multiply by the number.  

Example: Find 25% of $60.
.25 x 60 =$15

By changing the percent to a decimal and translating the word "of" to multiplication we have a simple solution.

Example: Find 40% of $30.
.40 x 30 = $12

 

We can now discuss sales price and discount.  

If the suit is regularly priced at $120, and it is marked 20% off the regular price. What does the suit cost?

Follow the above problems and begin by taking 20% of $120.
20% of $120 = .20 x 120 = $24.00


We call $24 the discount.


We calculate the sales price by taking the regular price $120 and subtracting the discount $24…
$120 – $24 = $96
The sales price and cost of the dress is therefore $96.

This classic lawnmower costs $85. What is its sale price?

$

 

The new CD from Atomic Fish is called 33% Solution.

If the solution was made up of 1800 ml, how many milliliters would constitute 33%?

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  writer:Kevin Gallagher