Significant Figures

Question 1

0.02 g

Answer 1

1 sig fig

Zeros at the beginning of a number are never significant; merely indicate position of decimal point

Question 2

0.0200 g

Answer 2

3 sig figs

Zeros that fall both at the end of a number and after the decimal point are always significant

Question 3

130 cm

Answer 3

2 or 3 sig figs

When a number ends in zeros but contains no decimal point, the zeros may or may not be significant

Question 4

1.03 cm

Answer 4

3 sig figs

Zeros between nonzero digits are always significant

Question 5

12 inches in 1 foot

Answer 5

Don’t worry about sig figs for exact numbers

I.e. A dozen eggs, people in a room, etc