Converting Units

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Converting Units

• KHDBDCM Factor Method

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Because it is based on 10, converting units is
easy when using metric quantities.
King kilo Henry hecto Died deca By bas
e Drinking deci Contaminated centi Milk mil
li
Move decimal left.
Move decimal right.
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K H D B D C M
Converting left to right move decimal right.
4 km to ? cm
K-H D B D C 1 2 3 4 5
SO move decimal 5 places right
4 km to 400000 cm
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Remember not to count the letterthat you start
with.If you are going from milli to kilo,
countK H D B D C- M

1. 5 4 3 2 1

and move the decimal 6 places to the left.
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Try these using K H D B D C M
3000 kg ? g
3 000 000 g
0.000009 mm ? hm
.000 000 000 09
750 daL ? mL
7 500 000mL
300 cm ? m
3 m
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Factor Conversion Other names Unit
Cancellation/ Dimensional Analysis
While the King Henry method is easy, it only
works when converting between kilo and milli
because these prefixes differ consecutively by
101.
For example, how would you change from Mg to cg
or km/hr to m/s ? Mega and hours arent in
the King Henry tragedy!
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In factor conversion, the idea is to multiply by
a factor equivalent to one, that cancels out
units, until the desired result is achieved.
4 yr ? min
x
x
4 yr 1
365 days 1 yr
24 hr 1 day
60 min 1 hr
x

4 x 365 x 24 x 60 min 2 102 400 min
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5 km/h ? m/s
x
x
5 km 1h
1000 m 1 km
1 h 60 min
1 min 60 sec
x

5000 m 3600 sec
5 x 1000 x 1 x 1 m 1 x 1 x 60 x 60 sec

1.4 m/s
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It may help to set up the units first and then
fill in the numbers
5 Mg ? cg
1 000 000
100
x
x
5 Mg 1
g Mg
cg g
1
1
5 x 1000 000 x 100 cg
500 000 000 cg