Add the rational numbers $$\dfrac{7}{-18}$$ and $$\dfrac{8}{27}$$

Asked by Aaryan | 1 year ago |  35

#### 1 Answer

##### Solution :-

Firstly we need to convert the denominators to positive numbers.

$$\dfrac{ 7}{-18} =\dfrac{ (7 × -1)}{ (-18 × -1)} = \dfrac{-7}{18}$$

The denominators are 18 and 27

By taking LCM for 18 and 27 is 54

We rewrite the given fraction in order to get the same denominator

$$\dfrac{-7}{18} = \dfrac{(-7×3) }{ (18×3)} = \dfrac{-21}{54}$$ and

$$\dfrac{ 8}{27} = \dfrac{(8×2) }{ (27×2) }=\dfrac{ 16}{54}$$

Since the denominators are same we can add them directly

$$\dfrac{ -21}{54} + \dfrac{16}{54 }= \dfrac{(-21 + 16)}{54} = \dfrac{-5}{54}$$

Answered by Sakshi | 1 year ago

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