Question

Write the following rational numbers so that they have same denominator:

$\frac{5}{12},\frac{8}{-21},\frac{-9}{28}$

Answer 1

Converting given fraction into equivalent fractions.

First covert $\frac{8}{-21}$ in standard form by multiplying numerator and denominator by $-1$so it will become $\frac{-8}{21}$.

To convert them in equivalent fraction we have to take the LCM of the denominators.

So, LCM of $12,21$ and $28$ is $84$.

Now convert the given rational numbers in equivalent fraction with denominator $84$.

$\Rightarrow \frac{5\times 7}{12\times 7}=\frac{35}{84},\frac{-8\times 4}{21\times 4}=\frac{-32}{84}$ and $\frac{-9\times 3}{28\times 3}=\frac{-27}{84}$

Now we can see that $\frac{35}{84},\frac{-32}{84}$ and $\frac{-27}{84}$ have the same denominator.

Hence, $\frac{5}{12},\frac{8}{-21},\frac{-9}{28}=\frac{35}{84},\frac{-32}{84},\frac{-27}{84}$.