Inequality notation to express error
I can calculate possible errors expressed using inequality notation a ≤ x < b.
Inequality notation to express error
I can calculate possible errors expressed using inequality notation a ≤ x < b.
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Lesson details
Key learning points
- When given a rounded number you can say what the biggest and smallest values of the unrounded number could have been.
- You can use $$a ≤ x < b$$ notation to express the range of values the unrounded number could have taken.
Keywords
Range - A range of values where every value in the range estimates to the given value.
Error interval - An error interval for a number $$x$$ shows the range of possible values of $$x$$. It is written as an inequality $$a ≤ x < b$$
Common misconception
Incorrect use of the error interval i.e $$a ≤ x ≤ b$$ or writing the error interval as $$a ≤ x > b$$
As a check, encourage students to round the upper limit interval by the degree of accuracy to see if it evaluates to the rounded number. Also, draw a number line to show the meaning of $$a ≤ x > b$$ and allow students to see the error.
To help you plan your year 8 maths lesson on: Inequality notation to express error, download all teaching resources for free and adapt to suit your pupils' needs...
To help you plan your year 8 maths lesson on: Inequality notation to express error, download all teaching resources for free and adapt to suit your pupils' needs.
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6 Questions
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