Question

Add the following rational numbers.
$\frac{4}{9},\frac{-1}{2}$ and $\frac{3}{-5}$

• A. $\frac{-49}{90}$
• B. $\frac{-59}{90}$
• C. $\frac{59}{90}$
• D. $\frac{49}{90}$

Answer 1

The correct option is B

$\frac{-59}{90}$

$\frac{4}{9}+\frac{-1}{2}+\frac{3}{-5}$

$=\frac{4\times 10}{9\times 10}+\frac{-1\times 45}{2\times 45}+\frac{3\times 18}{-5\times 18}$

(since LCM of 9, 5 and 2 is 90)

$=\frac{40}{90}$ + $\frac{-45}{90}$ + $\frac{-54}{90}$

$=\frac{40-45-54}{90}$

$=\frac{-59}{90}$