Significant Figure

-How to wirite the math anseers correctly-

Signifcant Digit
-the last number is uncertain
-E.g.---2.56      2.5(certain) 6(uncertain)
-wirte only one uncertain digits

Detail
-leading zero aren't counted
0.0000001 has 1 sig fig
-zero after decimal are counted
10050 has 5 sig fig
-trailing without decimal point aren't counted
12000000 has 2 sig fig

Exact number
-some quantities are defined as exactly a certain and no rounding require
Rounding Rules
-round the answers of digits using rules similar to math
-Digit   > 5 round up
62.47---62.5
62.43---62.4
62.45000003---62.5
62.4585---62.5