Significant Figures Examples with Answers
Fast worked examples for the exact numbers students search: 100, 1000, 0.00450, 90.010, and common rounding questions.
How Many Significant Figures Are in 100?
100 has 1 significant figure unless a decimal point or scientific notation is used to show extra precision.
How Many Significant Figures Are in 1000?
1000 usually has 1 significant figure. Learn why trailing zeros in whole numbers are ambiguous.
How Many Significant Figures Are in 0.00450?
0.00450 has 3 significant figures: 4, 5, and the trailing zero after the decimal.
How Many Significant Figures Are in 0.00208?
0.00208 has 3 significant figures because the middle zero is between non-zero digits.
How Many Significant Figures Are in 90.010?
90.010 has 5 significant figures. Zeros between non-zero digits and trailing decimal zeros count.
Round 7982 to 2 Significant Figures
7982 rounded to 2 significant figures is 8.0e+3, which avoids ambiguous trailing zeros.
Round 0.9978 to 2 Significant Figures
0.9978 rounded to 2 significant figures is 1.0 because the next digit rounds 0.99 upward.
Round 0.83 to 1 Significant Figure
0.83 rounded to 1 significant figure is 0.8 because the next digit is less than 5.
Round 123.456 to 3 Significant Figures
123.456 rounded to 3 significant figures is 123 because the fourth significant digit is 4.
Significant Figures in Scientific Notation
In scientific notation, significant figures are counted in the coefficient, not in the power of ten.