Question

the sum of two rational number in 4/21 if one of them is 5/7 find the other

Answer 1

let the rational number be x

and other be 5/7

According to given condition

$\: \: \: \sf{x + \frac{5}{7} = \frac{4}{21} }$

$\: \: \sf{x = \frac{4}{21} - \frac{5}{7}}$

$\: \: \: \sf{x = \frac{4 - 15}{21} }$

$\: \: \: \: \sf{x = - \frac{11}{21} }$