Your Basket 0 items - £0.00

Students learn how to find a percentage of an amount using calculator and non-calculator methods. As learning progresses they use decimal multipliers to find a percentage change and calculate a simple interest in financial mathematics.

This topic follows on from Fractions, Decimals and Percentages and takes place in Year 8 Term 5.

- Work interchangeably with terminating decimals and their corresponding fractions.
- Define percentage as ‘number of parts per hundred’, interpret percentages and percentage changes as a fraction or a decimal
- Interpret fractions and percentages as operators

- A percentage is a fraction out of 100, so 52% is the same as 52/100, which as the decimal equivalent of 0.52.
- Finding a percentage of an amount without the use of a calculator can be done by equivalent fractions or by finding 10% first. Another method could be to change the percentage to a decimal and multiply the decimal by the quantity
- If something increases by 20% the total percentage is 120%. This has an equivalent decimal multiplier of 1.2.
- If something decreases by 20% the total percentage is 80%. This has an equivalent decimal multiplier of 0.8.
- The original amount is 100%. To find the original amount students should use equivalent ratios.
- The word ‘of’ means to multiply.

Develop fluency

- Consolidate their numerical and mathematical capability from key stage 2 and extend their understanding of the number system and place value to include decimals and fractions.

Reason mathematically

- Extend their understanding of the number system; make connections between number relationships, and their algebraic and graphical representations

Solve problems

- Begin to model situations mathematically and express the results using a range of

formal mathematical representations.

Ratio, proportion and rates of change

- Solve problems involving percentage change, including:
- percentage increase,
- decrease
- original value problems
- and simple interest in financial mathematics

__Number__

- Define percentage as ‘number of parts per hundred’
- Interpret percentages and percentage changes as a fraction or a decimal and interpret these multiplicatively
- Express one quantity as a percentage of another,
- Compare two quantities using percentages,
- Work with percentages greater than 100%

October 26, 2018

In my experience, students, in general, find the concept of a mean straightforward to calculate and understand. However, the mean alone does not provide a complete picture of a set of data. To achieve this, a measure of spread is also required. The range is the simplest measure that can be used for this. Not […]

October 1, 2018

Solving problems with angles in parallel lines is like solving a murder mystery. One clue leads on to the next and the next until the murderer is found. However, it doesn’t end there. The detectives need to explain their reasoning in court using the relevant laws and procedures should the murderer plead not guilty. If […]

September 10, 2018

An equation is when one expression, or term, is equal to another. To solve an equation means to find the value of the variable (represented by a letter) that makes the two expressions equal. There are two types of equations for secondary school mathematics, linear and none-linear. In this blog I write about how I […]