Common Denominator/Examples
Jump to navigation
Jump to search
Examples of Common Denominators
Multiples of $12$
Multiples of $12$ are all common denominators of:
- $\dfrac 1 2$, $\dfrac 1 4$, $\dfrac 1 6$
Hence these fractions can be expressed as:
- $\dfrac 6 {12}$, $\dfrac 3 {12}$, $\dfrac 2 {12}$
$2$, $3$ and $7$
The fractions:
- $\dfrac 1 2$, $\dfrac 1 3$, $\dfrac 3 7$
have common denominators:
- $42$, $84$, $126$, $168$
and so on.
The lowest common denominator of $\dfrac 1 2$, $\dfrac 1 3$, $\dfrac 3 7$ is $42$.
$3$, $8$ and $6$
The fractions:
- $\dfrac 1 3$, $\dfrac 7 8$, $\dfrac 5 6$
all have a common denominator of $24$.
Hence:
\(\ds \dfrac 1 3 + \dfrac 7 8 - \dfrac 5 6\) | \(=\) | \(\ds \dfrac 8 {24} + \dfrac {21} {24} - \dfrac {20} {24}\) | ||||||||||||
\(\ds \) | \(=\) | \(\ds \dfrac {8 + 21 - 20} {24}\) | ||||||||||||
\(\ds \) | \(=\) | \(\ds \dfrac 9 {24}\) | ||||||||||||
\(\ds \) | \(=\) | \(\ds \dfrac 3 8\) |