The sum of two Rational numbers is $\frac{5}{3}$ if one of the numbers is $\frac{9}{20}$ find the other.

Let the other rational number be x.

According to the given data,

$\frac{9 }{20} + \mathrm{x} = \frac{5}{3}$

On rearranging the terms we get,

$\mathrm{x} =\frac{5}{3} - \frac{9 }{20}$

Since the denominators aren’t equal find their LCM.

LCM of 20 and  3 is 60.

Express the given rational numbers with a common denominator using the LCM acquired.

$\mathrm{x} = \frac{5\times 20}{3\times 20} -\frac{9 \times 3}{20\times 3}$

$\mathrm{x} = \frac{100}{60} -\frac{27}{60}$

$\mathrm{x} = \frac{73}{60}$

The other number is $\frac{73}{60}$.