What is significant figure and how to count it in a number? ?

Question

What is significant figure and how to count it in a number? ?

Answer 1

example:

3 significant figures

1249687 becomes 1250000

12129.3  becomes 12100

0.12345678750 becomes 0.123

simply put.. . . you choose the first n nonzero digits in the number that you are given. (use rounding off rules when it applies)

Answer 2

For example:

Solve to 3 significant figures:

1. 12/7 = 1.714285714285714285

Significant figures would be 1.71