Taking into account of the significant figures, what is the value of 9.99 m – 0.0099 m? \[NEET 2020 Phase I\]
Significant figures depend on least precise measurement. For 9.99 m (2 decimal places) minus 0.0099 m (4 decimal places), result 9.9801 m must be rounded to 2 decimal places as per subtraction rule in NCERT. So 9.98 m is correct, retaining 3 significant figures. Thus 9.98 m follows significant figure rules.
Ref: NCERT Class 11 Physics > Chapter 2: Units and Measurements > Topic: SI Units and Dimensional Formulae