year 8 maths

4J
Calculating percentage change, profit and loss
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4J Calculating percentage change, profit and loss
If you sell something for more than you paid for it, you have made a profit. On the other hand, if you sell
something for less than you paid for it, you have made a loss.
Retailers, business people and customers are all interested to know the percentage profit or the percentage
loss that has occurred. In other words, they are interested to know about the percentage change. The
percentage change provides valuable information over and above the simple value of the change.
For example:
Hat was $40
Discount $5
Now $35
The change for each situation is exactly the same, a $5 discount. However, the percentage change is very
different.
Hat was $40 . Discount 12.5% . Now $35 .
Cap was $8 . Discount 62.5% . Now $3 .
Cap was $8
Discount $5
Now $3
For the sunhat, there is a 12.5% change, and for the cap there is a 62.5% change. In this case, the
percentage change would be known as a percentage discount .
Let’s start: Name the acronym
What is an acronym?
How many of the following nine business and finance-related acronyms can you name?
• RRP
• CBD
• GDP
Can you think of any others?
• GST
• COD
• IOU
• ATM
• EFTPOS
• ASX
How about the names of two of the big four Australian banks: NAB and ANZ?
How do these acronyms relate to percentages?
The following three acronyms are provided for fun and interest only. Do you know what they
stand for?
• SCUBA diving • LASER gun • BASE jumping
Cambridge Maths NSW
Stage 4 Year 8 Second edition
ISBN 978-1-108-46627-1 © Palmer et al. 2018
Cambridge University Press
Photocopying is restricted under law and this material must not be transferred to another party.