Question

what number should be added to -7/9 so as to get -5/3​

Answer 1

$\Huge\tt\color{red}{Question:}$

$\tt What \: number \: should \: be \: added \: to \\ \tt \frac{ - 7}{9} \: so \: as \: to \: get \: \frac{ - 5}{3} \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \:$

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$\Huge\tt\color{red}{Answer:}$

$\tt Let \: the \: unknown \: number \: be : \: \: x \\ \\ \tt \frac{ - 7}{9} + x = \frac{ - 5}{3} \: \: \: \: \: \: \: \: \: \: \: \: \: \\ \\ \tt \implies x = \frac{ - 5}{3} - \bigg( \frac{ -7 }{9} \bigg) \: \: \: \: \: \: \: \: \: \: \: \: \: \: \\ \\ \tt \implies x = \frac{ - 15 + 7}{9} \: \: \: (LCM = 9) \\ \\ \tt \implies x = \color{red}{ \underline{ \boxed{ \bf \frac{ - 8}{9} }}} \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \:$

$\therefore \tt \frac{ - 8}{9} \: should \: be \: added \: to \: \frac{ - 7}{9} \: \\ \tt to \: get \frac{ - 5}{3} \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \:$

Answer 2

Answer:

Let the unknown number be x

-7/9 + x = -5/3

(-7+9x)/9 = -5/3

-7+9x = 9(-5/3)

-7+9x = -45/3

-7+9x = -15

9x = -15+7

9x = -8

x = -8/9