Question

ASSOCIATIVE PROPERTY OF ADDITION OF RATIONAL NUMBERS
Please answer with steps

THANK YOU

Answer 1

Given:

$( \dfrac{2}{5} + \dfrac{1}{4}) + ( \dfrac{ - 3}{5} )$

To find :

ASSOCIATIVE PROPERTY OF ADDITION OF RATIONAL NUMBERS

Solution :

$( \dfrac{2}{5} + \dfrac{1}{4}) + ( \dfrac{ - 3}{5} )$

LCM of 5, 4, and 5 is 20

$= > \dfrac{8 + 5 - 12}{20}$

$= > \dfrac{1}{20}$

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$\dfrac{2}{5} + (\dfrac{1}{4} \: + \dfrac{ - 3}{5} )$

=> $\dfrac{2}{5} + (\dfrac{1}{4} \: - \dfrac{ 3}{5} )$

LCM is 20

$= > \dfrac{8 + 5 - 12}{20}$

$= > \dfrac{1}{20}$

Your doubt clarification:

=> when the denominator 5 multiplies by 4 we get 20.

so, we need to multiply the numerator 3 with the same number 4 to get -12.