Mathematics for IGCSE & O level - Estimation (Section 3 - No. 16)
What does it mean for a digit to be 'significant'?
The digit is a zero.
The digit is a non-zero number.
The digit contributes to the value of the number.
The digit is to the right of the decimal point.
Paskaidrojums
A significant digit contributes to the overall value of the number.