Table of Conversion
The table of conversion is shown below. The factors under the arrows are factors of multiplication in going from a given unit to another unit on its left.
For example, in going from millimeter to centimeter, there is a factor of 10 under the arrow, hence:
1 centimeter = 10 millimeters
Another example, in going from micrometer to decameter, the factors under the arrows are:
- 1000 (from micrometer to millimeter)
- 10 (from millimeter to centimeter)
- 10 (from centimeter to decimeter)
- 10 (from decimeter to meter)
- 10 (from meter to decameter)
We now combine all factors and write:
1 decameter = 1000 × 10 × 10 × 10 × 10 micrometers = 10,000,000 micrometers
Factors of Conversion From the Table of Conversion
Table 1 above is used to determine the factor of conversion in order to convert from one unit to another.
Example 1
Convert \( 2.1 \text{ km} \) (kilometer) into \( \text{dam} \) (decameter).
View Solution
In what follows, we use the abbreviation \( \text{km} \) for kilometers and the abbreviation \( \text{dam} \) for decameter.
Using the factors in Table 1 above, kilometer which is to the left of decameter is given by:
\[ 1 \text{ km} = 10 \times 10 \text{ dam} = 100 \text{ dam} \]which may be written as:
\[ 1 \text{ km} = 100 \text{ dam} \]The above equality gives the following factors of conversion:
\[ \displaystyle \frac{1 \text{ km}}{100 \text{ dam}} = 1 \quad (I) \]and
\[ \displaystyle \frac{100 \text{ dam}}{1 \text{ km}} = 1 \quad (II) \]The above factors of conversion are used to convert \( 2.1 \text{ km} \) to \( \text{dam} \).
Write:
\[ 2.1 \text{ km} = 2.1 \text{ km} \times 1 \]Substitute \( 1 \) by \( \displaystyle \frac{100 \text{ dam}}{1 \text{ km}} \) which is the factor of conversion (II) found above because it is equal to 1:
\[ 2.1 \text{ km} = 2.1 \text{ km} \times \displaystyle \frac{100 \text{ dam}}{1 \text{ km}} \]Note that we have used factor (II) with \( \text{km} \) in the denominator so that it cancels with the \( \text{km} \) in the given \( 2.1 \text{ km} \).
Cancel \( \text{km} \) on the right:
\[ 2.1 \text{ km} = 2.1 \cancel{\text{ km}} \times \displaystyle \frac{100 \text{ dam}}{1 \cancel{\text{ km}}} \]Simplify:
\[ 2.1 \text{ km} = \frac{2.1 \times 100 \text{ dam}}{1} \]Evaluate:
Example 2
Convert \( 1,200,000 \text{ nm} \) (nanometer) into \( \text{dm} \) (decimeter).
View Solution
Nanometer \( \text{nm} \) is smaller than decimeter \( \text{dm} \) and therefore using the factors in Table 1 above going from \( \text{nm} \) to \( \text{dm} \), we write:
\[ 1 \text{ dm} = 1000 \times 1000 \times 10 \times 10 = 100,000,000 \text{ nm} \]which may be written as:
\[ 1 \text{ dm} = 100,000,000 \text{ nm} \]From the above we can write two factors of conversion:
\[ \displaystyle \frac{1 \text{ dm}}{100,000,000 \text{ nm}} = 1 \quad (I) \]and
\[ \displaystyle \frac{100,000,000 \text{ nm}}{1 \text{ dm}} = 1 \quad (II) \]Since we are given \( \text{nm} \) and we need to cancel them, we use the factor of conversion (I) because it has \( \text{nm} \) in the denominator which may be canceled.
The question in this example is to convert \( 1,200,000 \text{ nm} \) to \( \text{dm} \). Hence:
\[ 1,200,000 \text{ nm} = 1,200,000 \text{ nm} \times \displaystyle \frac{1 \text{ dm}}{100,000,000 \text{ nm}} \]Cancel \( \text{nm} \) on the right:
\[ 1,200,000 \text{ nm} = 1,200,000 \cancel{\text{ nm}} \times \displaystyle \frac{1 \text{ dm}}{100,000,000 \cancel{\text{ nm}}} \]Simplify:
\[ 1,200,000 \text{ nm} = \displaystyle \frac{1,200,000 \times 1 \text{ dm}}{100,000,000} \]Evaluate:
Examples with Solutions
Example 3
Convert \( 170 \; \text{dam} \) into \( \text{cm} \)
Example 4
Convert \( 12,500 \; \text{mm} \) to \( \text{hm} \)
Example 5
Convert \( 0.0023 \; \text{cm} \) into \( \text{nm} \)
Example 6
Convert \( 890,000 \; \mu\text{m} \) to \( \text{hm} \)
Exercises
Part A
Use Table 1 above to determine the factors of conversion and convert:
- \( 0.0102 \text{ Mm} \) to \( \text{hm} \)
- \( 0.3 \text{ nm} \) to \( \text{mm} \)
- \( 1200 \text{ m} \) to \( \text{Mm} \)
- \( 13200 \text{ dm} \) to \( \text{km} \)
- \( 0.002 \text{ Gm} \) to \( \text{km} \)
- \( 13200 \; \mu\text{m} \) to \( \text{dm} \)
- \( 0.003 \text{ dam} \) to \( \text{mm} \)
- \( 0.001 \text{ cm} \) to \( \text{nm} \)