Philosophy homework help. Quick Answer: Divide by 100.
To do any conversion, you find the relationship between the two units. In this case, 100 cm = 1 m.
This gives you two conversion factors:
##(100 cm)/(1 mm)## and ##(1 m)/(100 cm)##
Example
Convert 789 cm into metres.
First method
You multiply by a conversion factor: ##(100 cm)/(1 mm)## or ##(1 m)/(100 cm)##
Choose the one that gives you the correct units for the answer.
789 cm × ##(1 m)/(100 cm)## = 7.89 m
Note that the “cm” cancels out and leaves you with the answer in m. If you had chosen the other conversion factor, you would have gotten
789 cm × ##(100 cm)/(1 m)## = 78 900 cm²/m.
The strange units for the answer tell you that you have made a mistake.
Second Method
If you cant remember that 100 cm = 1 m, you can always use the definition of centi.
centi = 10?², so 1 cm = 10?² m
Then you can convert cm to m.
789 cm × ##(10?² m)/(1 cm)## = 7.89 m
Third Method
Here is an easy acronym for you to memorize.
khans hot dogs use dead cow meat ? k h d u d c m
The letters stand for kilo hecto deka (unit) deci centi milli.
‘u’ always stands for whatever base unit you are in, in this case, metres.
You want to go from c to the base unit u (metres). u is two places to the left of c, so you move the decimal point two places to the left.
789 cm= 7.89 m