1. In a decimal, the biggest digit has the greatest value.
Decimals
N1.5 Core Plenary
Which of these statements are not always true? Give examples of when they are not true.
A decimal with three decimal places is larger than one with only two decimal places.
To add two decimals, line the digits up starting on the right and add up, just as with
whole numbers.
In a decimal, the biggest digit has the greatest value.
Amber reads as ‘twenty-one point twenty-one’.
Is she correct? Why?
Preamble This activity is designed to tackle some common misconceptions surrounding decimals. Pupils should be encouraged to support their choices by examples: these will demonstrate their understanding and highlight any misconceptions. In some circumstances, pupils might profitably make up their own always true or not always true statements involving addition and subtraction.
Possible content Properties of decimals, including place value.
Resources No materials needed.
Solutions/Notes None of the three statements is always true is best read as ‘twenty-one point two one’, because the decimal part does not have a value of twenty-one.