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Percentage Applications

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12

Percentage Practice

Mixed Percentage problems: percentage of, Percentage increase & decrease, Finding the original value

Finding the % change in an amount

Khan Video Tutorial: Video 4 |

% practice A Class notes | pdf

% Change Class notes | pdf

% practice B Class notes | pdf

p353 Ex 24.04 p37 Ex 3.04

NuLake p22, 23, 24

 

 

Finding the Percentage Change

Remember to put the change over the ORIGINAL (starting value)

       

Question

 

Working

Answer

Gummy bears increase in price from 4c to 5c.
What is the percentage change?

(5-4)/4 x 100 =

25%

 

 

 

 

A shirt is on sale for $26, down from $34.
What is the percentage change?

(34-26)/34 x 100 =

23.5% (1dp)

 

 

 

A car devalues $800 in the last year. It is now valued at $3400
What is the percentage change?

Original value is
3400 + 800 = $4200

800/4200 x 100 =

19% (0dp)

 

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