Problem : 
How many significant digits does 5,273 have?
4
 
Problem : 
How many significant digits does 70,265 have?
5
 
Problem : 
How many significant digits does 60,286,000 have?
5
 
Problem : 
How many significant digits does 56.100 have?
5
 
Problem : 
How many significant digits does 40.0 have?
3
 
Problem : 
How many significant digits does 40 have?
1
 
Problem : 
If we know 3 digits of a measurement precisely, how many digits should we write 
down 
when we record the measurement?  How many significant digits will our 
measurement 
have?
4, 4.