Question

the sum of two ratial number is 9/16 .If one of them is -5/18 Find the other number​

Answer 1

Let the other number be x
Therefore x = 9/16 - (-5/18)
= (162 + 80)/144
=242/144
=121/72

Answer 2

We have,

• To determine the unknown number which when added with (-5)/18, results as 9/16

Here,

Let the unknown number be n.

Theñ,

$\to \: \bf{}n + \bigg(\frac{ - 5}{18} \bigg) = \frac{9}{16} \\ \\ \to \: \bf \: \: \: \: \: \: \: \: n = \frac{9}{16} - \bigg(\frac{ - 5}{18} \bigg)$

• Taking LCM of denominators (in RHS), which we get as 144

$\to \: \bf\: \: \: \: \: \: \: \: n = \frac{\big[9(9)\big] - \big[( - 5)(8) \big] }{144} \\ \\ \to \: \bf\: \: \: \: \: \: \: \: n = \frac{81 - \big[ - 40\big]}{144} \\ \\ \to \: \bf\: \: \: \: \: \: \: \: n = \frac{81 + 40}{144} \: \: \: \: \: \: \: \: \: \: \: \: \: \: \bigg \{ \because (\green - ) \times ( \green- ) = ( \pink+ ) \bigg \} \\ \\ \to \:\bf\: \: \: \: \: \: \: \: n = \red{ \frac{121}{144} }$

Thus,

• 121/144 is the required number which on adding with (-5)/18, results as 9/16.