Teaching Guidance
Students should be able to:
- perform money calculations, writing answers using the correct notation
- round numbers to the nearest whole number, 10, 100 or 1000
- round numbers to a specified number of decimal places
- round numbers to a specified number of significant figures
- use inequality notation to specify error intervals due to truncation or rounding.
Notes
Including appropriate rounding for questions set in context.
Students should know not to round values during intermediate steps of a calculation.
Students should know that some answers need to be rounded up and some need to be rounded down.
Students should know that some answers are inappropriate without some form of rounding, for example 4.2 buses.
See N14
Examples
1 / How many 40-seater coaches are needed to carry 130 students?
2 / 120 people take their driving test in a week.
71 pass.
Work out the percentage of those who pass.
Give your answer to one decimal place.
3 / 1127 people pass their driving test in 39 weeks.
Calculate the mean number of students who pass in one week.
Give your answer to one significant figure.
4 / A rectangle has a length of 3.4 cm
The length is given to 1 decimal place.
Use inequalities to write down the error interval due to rounding.
5 / A parcel has a mass of 28.6 g
This mass has been truncated to 1 decimal place.
Use inequalities to write down the error interval due to truncation.
6 / Jack says he is 12 years old.
Use inequalities to write down the error interval of his age.