Ratio, proportion and percentages
Ratio, proportion and percentages

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Ratio, proportion and percentages

3.2.1 Try some yourself

Activity 20

Convert each of the following to percentages. Round off the percentages to whole numbers.

  • (a)

    • (i) 0.8

    • (ii) 0.21

    • (iii) 0.70

    • (iv) 2.4

  • (b)

    • (i)  

    • (ii)  

    • (iii)  

    • (iv)  


  • (a)

    • (i) 0.8 = 80%

    • (ii) 0.21 = 21%

    • (iii) 0.70 = 70%

    • (iv) 2.4 = 240%

  • (b)

    • (i)    = 0.5= 50%

    • (ii)    = 0.125=12.5% 13%

    • (iii)     0.1111 11%

    • (iv)     1.143 114%

Activity 21

In the election in Example 11 the Average party gets 2100 votes. In the previous election they had 10%. Find the swing.


2100 out of 5000 is

× 100% = 42%.

The swing is 42 − 10 = 32 percentage points.


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