Question

Verify commutativty of addition of rational numbers for each of the following pairs of rotional numbers: 

\[4\ \text{and} \frac{- 3}{5}\]

Answer 1

\[\text{We have  4 and} \frac{- 3}{5} . \]
\[ \therefore 4 + \frac{- 3}{5} = \frac{4 \times 5}{1 \times 5} + \frac{- 3}{5} = \frac{20 - 3}{5} = \frac{17}{5} \]
\[ \frac{- 3}{5} + 4 = \frac{- 3}{5} + \frac{4 \times 5}{1 \times 5} = \frac{- 3 + 20}{5} = \frac{17}{5} \]
\[ \therefore 4 + \frac{- 3}{5} = \frac{- 3}{5} + 4\]
\[ \text{Hence verified} . \]