Converting units of measure - prefixes

 

When we put prefixes in a line from large to small we get something like this

 

 

Mega kilo hecto deca BASIC deci centi milli micro nano

(M) (k) (h) (da) UNIT (d) (c) (m) () (n)

1,000,000 1,000 100 10 1 .1 .01 .001 .000001 .000000001

 

106 103 102 101 100 10-1 10-2 10-3 10-6 10-9

 

 

 

 

 

 

 

 To do a conversion all you need is an equality. Heres a few examples of how to:

1. 5250 m (meters) = how many km (kilometers)?

 

a. The equality needed is:

1 km = 1000 m

b. Now use the equality as a fraction in a grid:

5250 m

1 km

Ans

5.25 km

1

1,000 m

 

 

 

2. 346 hL (hectoliters) = how many L (microliter)

 

a. 1 hL = 100 L and 1 L = 10-6 L

(Notice in the equalities we substituted 100 for h, and 10-6 for .)

b.      Now we use these equalities in our grid:

346 hL

100 L

1 L

= 34,600 L

= 3.46 x 1010 L

1

1 hL

10-6 L

= 10-6

 

 

3. 489 mg = how many kg ?

 

a.       1 mg = 10-3 g and 1 kg = 1 x 103 g

b.      now we use both equalities in our grid:

489 mg

1 x 10-3 g

1 kg

= 489 x 10-3 kg

= 489 x 10-6 kg

1

1 mg

1 x 103 g

= 1 x 103

 

 In scientific notation this would be = 4.89 x 10-6 kg