constant of proportionality
What constant of proportionality means in Mathematics GCSE, as defined for AQA, Eduqas, Pearson Edexcel.
Definitions of constant of proportionality
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Reference: AQA
The constant k in the form X = kY or X = k/Y, found from a given pair of values and used to calculate an unknown value.
The fixed value k found by using the pair of values you are given, written into the rule y = kx or y = k/x.
The value k, found by substituting the given pair of values to form an equation in k.
The constant k in y = kx or y = k ÷ x, found by substituting a known pair of values.
The constant value (usually denoted as $k$) that relates two proportional variables.
Topics that use constant of proportionality
- Ratio, proportion and rates of change (AQA GCSE)
- Ratio, proportion and rates of change (Eduqas GCSE)
- Ratio, proportion and rates of change (Pearson Edexcel GCSE)
Related terms
- Compound Measure
- Multiplier
- compound interest
- compound unit
- Density
- direct proportion
- equality of ratios
- inverse proportion
Using constant of proportionality in the exam
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