When making estimations, it is important to remember the types of calculations you are making.
It is not realistic to estimate that a person weighs 1500 pounds. That is impossible. It is instead more realistic to estimate that a person weighs 150 pounds.
*Estimates should be based on what you already know about the world around you
It is appropriate to make estimates in measuring length. Some rulers only measure to the nearest centimeter; however, an object might be seen as slightly over eight centimeters, therefore, it is appropriate to estimate that the length of the object is 8.1 cm.
The following are the universal accepted measurements of different quantities.
The gram (g) is the SI measurement of mass.
The meter (m) is the SI unit of length
The second (s) is the SI unit of time
The liter (l) is the SI unit of volume.
These basic units can be made into derived units
Common prefixes:
Milli: 1000 mm = 1m
Centi: 100 cm = 1m
Deci:10 dm = 1m
Deca:1/10 m =decameter
Kilo: 1/1000 m = 1km
Ex. How many kilometers is two meter?
To do this since one meter is equal 1/1000 of a kilometer, 2 must be divided by 1000, to get 2m = .002 km, 2 x 10-3 km.
