Percentages - financial calculations part 1

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You may wish to review the material from the previous learning bite. It is important to know this before attempting this learning bite
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The way we can calculate a mark-up or discount is to calculate a percentage increase (mark-up) or decrease (discount).

In order to do these calculations, there are some important points to note. The first is that an unchanged price equates to 100% of the original price. Using this convention, a decrease in price of 20% would equate to 80% of the original price. A mark-up of 30% would be 130% of the original price.

Access the materials below from Mathletics to gain a better understanding of increasing and decreasing by a percentage amount. The solutions are also included.

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Now that you have learnt how to increase and decrease an amount by a percentage, you can begin to apply this to financial problems.

The following is from the Oxford Big Ideas 8 text book.

at this point, just try the following problems:

Now try these: questions 1 and 2

Explore: questions 1, 2, 3 and 4

For the Explore questions, you will need to know what commission is. It is the percentage amount a salesperson earns on sales he/she makes. For example, a 10% commission on a sale of $300 is the same as saying 10% of 300, which is 30. The salesperson would earn a commission of $30 in this case.

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Simple interest is another useful application of 'percentage increase'. Interest is an amount you earn on money invested, and also refers to the 'extra' money you pay back when you borrow money. Yes, it costs money to borrow money!

let's say you borrow $1000 from the bank. If you were charged 5% per annum (each year) in interest, at the end of the year, you would have to pay back the $1000 plus 5%. This equates to a total of 1000 plus 50 which is $1050 to be paid back after a year.  

Edit   Delete - Last Modified By: dna at 14/04/2014 10:57:36 AM