Maths · OCR Paper 2
Standard Form and Accuracy
The number skills tested on OCR Paper 2: standard form, calculating with standard form, rounding and estimating, error intervals and bounds, and recurring decimals.
Lessons
Ticks are remembered on this device only.
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1
Standard Form
Writing very large and very small numbers in standard form, converting back, and comparing and ordering them.
9 terms -
2
Calculating with Standard Form
Multiplying, dividing, adding and subtracting numbers in standard form, and solving problems in context.
9 terms -
3
Rounding and Estimating
Rounding to decimal places and significant figures, estimating calculations, and spotting over- and underestimates.
9 terms -
4
Error Intervals and Bounds
Writing error intervals for rounded and truncated numbers, and finding upper and lower bounds of calculations.
9 terms -
5
Recurring Decimals and Rational Numbers
Converting fractions to recurring decimals, writing recurring decimals as fractions, and telling rational from irrational numbers.
9 terms
Key terms in this chapter
All 45, gathered from every lesson.
- Standard form
- A number written as \(A \times 10^n\), with \(A\) at least 1 and less than 10.
- Power of 10
- 10 raised to a whole-number power, such as \(10^4\).
- Index
- The small raised number that shows the power.
- Decimal point
- The dot that separates whole numbers from fractions.
- Significant figure
- A digit that carries meaning, starting from the first non-zero digit.
- Ordinary number
- A number written in the usual way, not in standard form.
- Negative power
- A power below zero, which gives a number between 0 and 1.
- Order of magnitude
- The power of 10 that shows roughly how big a number is.
- Scientific notation
- Another name for standard form.
- Standard form
- A number written as \(A \times 10^n\), with \(A\) at least 1 and less than 10.
- Law of indices
- A rule for combining powers, such as adding the powers when multiplying.
- Power
- The small number showing how many times a number is multiplied by itself.
- First part
- The number between 1 and 10 in standard form.
- Adjust
- To change the first part and the power so the answer is in standard form.
- Order of magnitude
- The size of a number, shown by its power of 10.
- Unit
- The measure that goes with a number, such as metres.
- Rate
- A quantity per unit of another, such as a speed.
- Total
- The result of adding or multiplying all the parts.
- Rounding
- Replacing a number with a simpler one that is close to it.
- Decimal place
- A position after the decimal point.
- Significant figure
- A digit that counts, starting from the first non-zero digit.
- Estimate
- An approximate answer found by rounding.
- Approximately equal
- Nearly equal, shown by the symbol \(\approx\).
- Overestimate
- An estimate that is bigger than the true value.
- Underestimate
- An estimate that is smaller than the true value.
- Nearest
- The closest value of a given type, such as the nearest 10.
- Place value
- The value of a digit because of its position.
- Error interval
- The range of values that round to a given number.
- Lower bound
- The smallest value in an error interval.
- Upper bound
- The value that the interval goes up to but does not include.
- Truncation
- Cutting off digits without rounding.
- Limit of accuracy
- The bounds of a measurement or rounded number.
- Inequality
- A statement using signs such as \(<\) and \(\leq\).
- Rounding
- Replacing a number with a simpler one that is close to it.
- Half a unit
- Half the size of the rounding unit.
- Measurement
- A quantity found by measuring, which is never exact.
- Terminating decimal
- A decimal that stops after a certain number of digits.
- Recurring decimal
- A decimal in which one or more digits repeat for ever.
- Dot notation
- Dots over repeating digits to show a recurring decimal.
- Rational number
- A number that can be written as a fraction of two integers.
- Irrational number
- A number that cannot be written as a fraction.
- Surd
- An irrational root, such as \(\sqrt{2}\).
- Integer
- A whole number, positive, negative or zero.
- Simplest form
- A fraction that cannot be cancelled further.
- Repeating block
- The digits that repeat in a recurring decimal.