Prealgebra: Measurements

Problem : How many significant digits does 5,273 have?

Problem : How many significant digits does 70,265 have?

Problem : How many significant digits does 60,286,000 have?

Problem : How many significant digits does 56.100 have?

Problem : How many significant digits does 40.0 have?

Problem : How many significant digits does 40 have?

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?