Ordering FDP
How do I put fractions in order of size?
- When comparing only fractions, write them over a lowest common denominator
- For , the lowest common denominator is 60
- So change them to and then order them by their numerators
- From smallest to largest:
- Rewrite in their original form:
How do I put fractions, decimals and percentages in order of size?
- When comparing a mixture of fractions, decimals and percentages, change everything into decimals
Which symbols can I use?
- Rather than just listing values in order, symbols can be used to compare them
- For example,
- Recall that means greater than and means greater than or equal to
- Similarly, means less than and means less than or equal to
- You may also see and (which means "not equal to")
Examiner Tip
- A calculator can be used to quickly convert any quantities into decimals
- However, this type of question will often be in the non-calculator paper
Worked example
Without use of a calculator, write these numbers in order, starting with the smallest.
As they are all fractions, write them with a common denominator
The lowest common denominator is be 75
Rewrite each fraction with a denominator of 75
Compare and write in order from smallest to largest
Rewrite in their original form
Worked example
Without use of a calculator, write these numbers in the spaces below.
..... < ..... < ..... < .....
As there is a mixture of fractions, decimals, and percentages, rewrite each as a decimal
0.8 is already a decimal
Convert 78% to a decimal by dividing by 100
Convert to a decimal by either using short division, or halving three times
so
Convert to a decimal by using short division
so
Write them all with 3 decimal places to determine the order
Rewrite the decimals in order
Rewrite in their original form, and recall that < means "less than", so the smallest value will be first
If a calculator was allowed for this question, it could be used to find and more easily