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15 
Ratio increase & scaling Increasing of decreasing given a ratio Calculating the cheapest option or best value 
Recipe example  pdf p62 Ex 4.05 NuLake p28, 29 
Splitting up given a ratio 

Example 1 
Share an interitance of $48 into the ratio 5:1 
Steps 

5 + 1 = 6 parts 
1) Add the ratio 'parts' together (how many 'parts' total?) 
$48 ÷ 6parts = $8 
2) What is 1 'part' worth? 
5:1 
3) Share the ratio 
5 x $8 : 1 x $8 

$40 : $8 
Write the ratio in the correct order 
Example 2 
Bob & Bill build a boat. Bob works for 12hr and Bill works for 30hr 
Steps 

12 + 30 = 42 parts 
1) Add the ratio 'parts' together (how many 'parts' total?) 
$840 ÷ 42parts = $20 
2) What is 1 'part' worth? 
12:30 
3) Share the ratio Bob:Bill 
12 x $20 : 30 x $20 

$240 : $600 
Bob gets $240 and Bill gets $600 